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Lloyd Sealy Library
John Jay College of Criminal Justice

How to use the library: How to search library databases

Boolean searching

Most library databases are best searched using Boolean searching.  That is, you choose words that best describe your topic ,and connect them with either AND, OR or NOT.

Boolean searching is named after a 19th Century mathematician, George Boole.

corpses AND insects     retrieves records containing both words



corpses OR cadavers     retrieves records containing either word



(corpses OR cadavers) AND insects

retrieves records containing the word insects

 as well as

either the word corpses or the word cadavers


insects NOT beetles
when you want insects but not beetles

beetles NOT automobiles
when you want beetles but not cars

fingerprinting NOT dna
when you want that older technology:



Use truncation – in most databases, the truncation symbol is an asterisk.

corps* will retrieve corpse and corpses.

emigra* will retrieve  emigrant, emigrants, emigration.


The Boolean Machine is a tool for visualizing the effects of Boolean operators on keyword searches.

How Do I Choose Search Terms?

Once you have narrowed down your topic and come up with the research question your paper will explore, identify the main concepts in your query. Use these concepts as your search terms (keywords).

See examples below.


Research question:

   How does domestic violence affect children?                                

Compose your search:
   domestic violence
and  children

How else might you compose your search?
   family violence
and  children 

Research question:
   Does providing employment opportunities to ex-prisoners
   reduce the risk they will re-offend? (= recidivism).

Compose your search:
and employment and recidivism
and  employment and recidivism

Perhaps broaden the search to find more about recidivism in general:

and causes


Use subject headings to increase relevancy of results

When you see a good article in your list of results, look at the subject headings describing that article:

Some databases will show you a list of subject headings beside your result list. You can choose a subject, then click update, to get a list of articles described using that particular subject heading. 

Or just do another search using the words used in the subject headings. e.g.

carrion insects and biodegradation

Or perhaps the subject heading is phrased in an unexpected way? Perhaps it is homicide rather than murderAdolescents rather than teens

Choose a database

Search box from homepage: Databases tab pre-selected

On the Library's homepage, select the Databases tab in the main search box.

Open the dropdown menu for Select from popular databases, which lists the most-used databases at John Jay. You can also find databases by subject or by title.

If you wish to find articles in a given academic discipline, view databases by subject. For example, under Criminal Justice, you will see a list of databases that specialize in the topic.

If you want to go to a specific database whose name you already know, view databases by title