Search using Boolean operators


Searching bibliographic databases

Decide what words best describe your topic. Connect them with either AND, OR, or NOT.

corpses AND insects retrieves records containing both word

beetles OR flies 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 the old-fashioned type

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

corps* will retrieve corpse and corpses.

When you find relevant articles, look at the subject headings in each record. Subject headings are chosen from a controlled vocabulary. Perhaps the subject heading is phrased “entomology” rather than “insects”? If so, search again, replacing “insects” with “entomology”.

Further reading

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