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General Science

Searching online best strategies, Boolean and Concept building


You can use the search operators AND, OR and NOT to combine search terms. These are the most commonly known and used boolean operators.

The operators AND and NOT limit the number of results from a search. The operator OR does the opposite; it increases the number of results.


  • Endangered AND birds : searches for sources that have both these two words.
  • Endangered OR birds : searches for sources with the word 'endangered' OR the word 'birds'. This search will produce more results. (Tip: the operator “OR” can also be used to include different spellings and translations or synonyms in the search).
  • Endangered NOT birds : searches for the word ‘endangered’ and excludes the any sources that also has the word ‘birds’.

To see how this works, take a look at The Boolean machine. Move your cursor over the operators AND, OR and NOT to see how they determine your search.

You can also combine more than two search terms. Use brackets to indicate the priority. For example (Money OR inflation) AND banking.

Short videos on searching information:

Boolean search basics:

Why cant I just 'Google it', from RMIT libraries

One perfect source?

Database search concepts and Boolean:

Example: I want to search for an essay titled: "Discuss the effect of antioxidants on athletic performance"

I can do an 'Advanced Search' this means there will be a number of concept search boxes available with AND between them

Remember the more concepts we combine the fewer and more specific the search results

Within a concept box we can add different variants of similar words (Synonyms) with OR between them to increase the search results

Decide on your research question:
The research question should be a topic that is searchable and not too broad or too specific. Do sample exploratory searches on library databases before finalizing your topic
Decide how broad or narrow your scope will be: 
Having picked your topic decide on the coverage and specificity of your research topic, will you focus on all topic areas or just one, can you narrow the topic, what years will you cover.
Decide where you will search
The library has a number of specialist databases, see the descriptions under each database
Conduct your search: 
Do look at the tabs there also on 'Advanced Searching' and on 'Keyword and database search tips' 
Remember to source all the relevant key words for your topic 
Remember to keep track of your references; Mendeley or Zotero are useful tools for this.
Review the literature
You may need to critically evaluate the sources and references you use; analyse the research methodologies used and any bias or exclusions and compare with other relevant studies 


Finding Information

Assignment search example: Discuss the effects of exercise on psychological stress so the main search concepts are 'exercise and stress'

Sources include Books / Academic Articles/ Statistics and websites


Books can be searched on the TUS Midlands Library OPAC catalogue: The search can be limited to  Ebooks or to physical books only using the tick boxes below the advanced search. 

The OPAC catalogue record (example) will show the call number of the shelving location of physical books; also books on similar topics can be browsed under the Subject entry on the catalogue record.

e-books are also available on the OPAC search: Just click on the link 'Online access click to view' in your OPAC catalogue search results, this will redirect to the specific e-book record on the E book Central database

E books Central is also available directly on the TUS Midlands library website under the Tab - Collections - E books - Ebook Central

Academic Articles

One can also check for academic articles on your research topic (as an example if doing an essay on the effect of physical activity on psychological stress, you might use keywords such as, 'exercise and stress' in a database search)

We can use the Discover search on the main library web-page to search for articles.

Note:You will need to login to use this resource.

Just add your search concepts to the Discover search box (Exercise AND stress) and links to academic journal articles will be available in the search results.

The journal articles retrieved may be available directly though our TUS Midlands library databases or by links to free open access articles.

Refining a search result in Discover:

If a lot of results are provided, the concepts can be narrowed: There is a 'Date' and subject limiter on the left,  

One can also click on the 'Advanced search' option under the search box once a search is performed in Discovery, also one can 'Select a field' on the drop-down tab on the right of advanced search (example 'Subject terms search'or or 'Abstract ').

One can also change the search keywords, for example using search keywords such as Jogging or running instead of exercise.

Articles can be opened by following the links in Discover to find the full text if available.

Other sources:

Examples of other sources that can also be searched are: Statistics, Information Guides and websites.

See the Library website and tabs - Collections - Theses, there are some useful links here include Lenus, Ethos (online theses) Rian and Research@Thea

If doing a Google search be careful to evaluate your source (see the Critical Evaluation tab on most of the Science Libguides)

Another good source for government sources and reports is Google advanced search as the Domain limiter there will allow any search be limited by national government (, etc) or education (edu) websites.


In any stage of you search if you need help or support you can contact the library staff at or Email:


Advanced Searching on EBSCO from ISU libraries


Some more tips on advanced searching: TUS: Midlands

Advanced Searching skills and Search Concepts: using search concepts in a library database

Example topic: “The effect of supplements on sports performance”

Go to Library - Collections - Databases - open EBSCO Academic Search Complete

At this stage you can add some extra EBSCO databases to allow a cross search by clicking on 'Choose Databases' at the top of the web-page:

For this topic we add: Cinahl, SportsDiscus; Medline (full descriptions of database content are on the library databases page).

Note: It is useful to do a personal sign in to any database. A personal sign-on allows us to save relevant searches and also to have any new results of relevant searches automatically emailed by setting up a search alert.

To save a search or to set up an alert after the personal sign-in on EBSCO, just click on 'Search history' and then click on the relevant search to select it.

Example search; Supplements and Sport performance

Advanced search allows a separate search box for each concept, so synonyms (words that have similar meanings) can be added with OR between them in each search concept box.Examples of synonyms are Supplement or Antioxidant or "nutrition support"

In EBSCO one can also increase the results obtained by clicking on the 'apply related words' box.

Inverted commas indicates a search phase, (e.g. "tennis elbow"); and this means that only that exact phase will be retrieved in a search.

Other options to aid in a search:

Proximity Search:

Means that the words need to be within a certain number of words to each other to be retrieved. 

 e.g. Nutrition N4 support; means these words have to be within 4 words of each other in the documents searched

Truncation Search:

This will search for all possible ending of a word for example Supplement* (so, supplement, supplements, supplementation or any other word with the stem 'supplement'), n* will search for every word that starts with the letter n.

 e'g Supplement* with a star * sign will search for supplement or supplements

So our full example search is as follows:

(Supplement or antioxidants or Nutrition N4 Support)


(sports or athletics or "physical activity" or exercise)


(benefit or performance or impact)

N.B. Brackets indicate a separate search box in advanced search.

Result: This gives (at time of search): Search Results: 1 - 10 of 2,654.

Strategies to focus these results

In EBSCO under 'Page options' we can change the results per page to 50

These results are ranked by relevance so more relevant articles will be on top in the results page.

Search Fields: In case of a lot of results, it is also often useful to rerun the search, - change the 'Select a field' opposite the search boxes to Abstract or Subject or even to a 'Title' search).  It is also possible to limit your search to a particular journal.

Subject search:  A search can be limited by clicking on the specific subject suggestions (on the left of results in EBSCO)

Note: This strategy will increase search specificity but you may also miss out on relevant results.

Search Filters are on the left of the results screen:

Filter by Date; - for example limit results to 'last 5 years'

Filter by Subject: It is possible also to ‘search within a search with a listed option of subject terms’ (on the left of the results page). This can make the results very focused as is is a specific subject search within a search already performed.

NB : One can also filter before a search by using the particular database 'Limiters' under the search boxes (Document type, date, sex etc)

Other strategies include: Examination of keywords and subjects occurring in relevant articles and using these in subsequent searches. (An example for our search, might be a keyphrase, such as "dietary supplement").

Looking at the reference list of very relevant articles, and searching for some of those specific articles. If you find a relevant article in a reference list you can simply enter the article title into Discovery or do a 'Publication search' (for our journal title holdings of that journal) also on the main library web-page.

Other Resources:

Google advanced search with domain limiter for government reports; / education reports etc: Google Scholar with cited by links: Library guides: Open Education Resources (OER): Library These tab with additional resource links: Library contacts for specific queries.

Using search aids:

Most databases allow you to use * as a truncation symbol; for example Nurs* will search for all words starting with Nurs, typically Nurse, Nurses, Nursing

Most databases allow the use of ? as a wildcard, for example Wom?n stands for Women or Woman

Most databases allow phrase searching with the use of inverted commas, e.g. "Nutrition support"

Many databases allow proximity searching but the method differs in different databases, e.g, In EBSCO  Nutrition N3 Support means that the words need not be in a phrase but need to be within 3 words of each other to be retrieved

Review Articles: When reviewing the literature it can be useful to look at review articles; some databases such as PubMed and PsycINFO allow one to use a search limiter for review articles; alternatively the search term 'Review' can be added as an extra search concept

Citation tracking: Also called Citation analysis, or Cited reference searching, is a way of measuring the relative importance or impact or an author, article, or publication, by counting the number of times that author, article, or publication has been cited by other works. Databases such as PubMed; Scopus and Google Scholar have a 'Cited by' link 


Writing a Search Statement: You can use 'Concepts' and Boolean logic to create a Search Statement for your write up, for example a search strategy for the essay topic, 'Supplements are a valuable aid to athletic performance, Discuss?',  might be as below

(Antioxidants or supplements or "nutrition support") AND (Sports performance or athletic performance) 

Truncation symbols and proximity operators in use for different databases

AIT Library Database searching: Notes and tips

Click: Collections tab and then on Databases

Main Science databases include the EBSCO databases (CINAHL, Academic Search, SocINDEX, SportDiscus, Medline) and Proquest databases (Health Research premier, PsycArticles, PsycInfo), also, Scopus, Wiley Online, Sage, Taylor & Francis, Oxford Journals Collection, JSTOR, Cambridge Journals Online and Science Direct Database; and free databases such as PubMed and Google Scholar.


Highwire’ and ‘BioMed Central’ for examples of good open access databases. 

For more free resources, click on the 'Collections' tab and then on the ‘Theses’ link for free resources such as RIAN, Ethos (theses) and LENUS

N.B. 'Discover' on the main library web-page is not a database but a search engine which searches across different databases however the searching principles are the same:

All TUS Athlone Science & Medicine databases:

Academic Search Complete (Ebsco)
Anatomy TV
BMJ Best Practice
Cambridge Journals Online
ClinicalKey Student Nursing (eBooks)
Clinical Skills (Interactive nursing skills based)
Clinical Sports Medicine Collection
CINAHL with Full Text (Ebsco)
The Cochrane Library (Freely available)
Dentistry and Oral Sciences Source
Health Research Premium
Irish Medicines Formulary
JOVE Video Journal, Science Education & Textbook
Kanopy (Film documentaries)
Medicines Complete
Oxford Journals Collection
PILOTS: Published International Literature On Traumatic Stress
PubMed (Freely available)
Research Professional
Sage Premier 2021 Collection
Sage Research Methods
Social Sciences Premium Collection
SocINDEX with Full Text
Wileys Journal Database



KEYWORD SEARCH: strategies and Hints

See: Information Literacy Tutorial at TUS Midwest

Decide on keywords, which cover all or part of the meaning of your research.

Initially select 2 or 3 words which together sum up the meaning of the essay (or part) and use these in separate search boxes

When selecting keywords start simply; use two or three simple keywords or phrases; then you can adjust the search depending on the number of results. 

In many databases (and Google) you can put key phrases in inverted commas such as “student nurse” or “communication barriers”; this will ensure that the phrase, rather than the separate words are searched. 

If you get a lot of results make the search more specific by adding another keyword or by changing the search parameters to TITLE or ABSTRACT.

After the preliminary search type you should expand your keywords. Eventually, you may have 10 or more different keywords that you can try in a combination of 2 to 3 at a time in the different databases. Remember different keywords will give optimum results in different databases.

Look at the keywords or subject terms in relevant articles in your results and consider adding these to your search keyword list.

In some databases certain SUBJECT searches will be suggested depending on your initial search which can be very helpful. Remember a SUBJECT is what the main topic of an article is, so all the results will be relevant. In EBSCO simply click on the subject thesaurus or Subject Major heading on the left of the main screen

You may then decide to rerun the search with different keywords or Subject areas

Also search Discover and Google scholar for the article as these link to other free resources

For medical / Biological articles also check PubMed and click on the free full-text limiter – this limiter is on the left of the results screen.

To look at the full text for any article click on PDF full-text link – you can email articles to your student email from most databases or print or save using the print and save shortcuts. 

You can save results and also set up email subject alerts by setting up a personal login on the library databases 

If you find a very relevant article in any database do check the reference list at the end of the article; you can search for a journal title on the main library page to see if the library holds the journal referenced or if the library has a link to it. 

NOTE: If the journal-title is in abbreviated format simply type the abbreviation into a google search with the word ‘journal’ beside it and the full title will appear

Pubmed has a ‘Related citation’ link on its searches to help you find similar articles

Google scholar has a ‘Cited by’ and Cited in’ function which can also be used to find similar material.


Zotero is a reference manager will allow you to organise your references and to download book and article references into your Zotero library

Mendeley Graphic

Mendeley is a reference manager software founded in 2007 by PhD students and acquired by Elsevier in 2013

Please note: The newer Mendeley download is called Mendeley Reference Manager; if you download this on a college laptop then download the word plugin through Microsoft Store from this link .  To complete the install for the word plugin you will need to login to Office 365, just follow the prompts, and use your college signon.

EndNote is another reference management software package, used to manage bibliographies and references when writing essays, reports and articles.


Statistics relating to Ireland: 

International statistics