Using keywords to search:
Include important words and phrases.
Describe a central or major concept.
Use broader and more general words for more results. "birds of prey" "raptors"
Use narrower and more specific words for fewer results. "red-tailed hawk" "peregrine falcon"
Using subject headings:
For discipline "controlled vocabularly."
To discover the subject headings for your topic do a keyword search.
Then browse the results and note the "assigned" subjects, descriptors or major concepts.
After that, redo your search with the "assigned" subjects, descriptors or major concepts.
AND, OR and NOT
Using Boolean Operators: AND, OR, and NOT
Connect search terms, whether keywords or subject headings, to narrow or broaden the results. AND is the default operator for most databases. Google will automatically put an AND between search terms.
To find all the words. To narrow your search.
cats AND dogs
To find any of the words. To broaden your search.
cats OR dogs
To narrow your search.
cats NOT kittens
From Basic to Advanced Searching
While searching most, but not all databases, you can go to a basic search page and perform an advanced search there. Be sure to capitalize AND, OR and NOT. Use quotation marks for phrases and use parentheses as needed. See the box below for more detail.
Use OR to search for similar concepts; and NOT to exclude a sub-topic.
"global warming" OR "climate change"
(("global warming" OR "climate change") NOT economics)
Use AND to interrelate concepts; and NOT to exclude a sub-topic.
"global warming" AND "sea level"
(("global warming" AND "sea level") NOT estuaries)
Example, EBSCOhost basic search screen:
Sometimes, + is used instead of AND and - is used instead of NOT.
Example, WorldCat Local Discovery basic search screen.
From Basic to Advanced Searching... Using Phrases
Notice how keeping a phrase in quotes or parentheses changes your search results, if at all.
For one search you may find that a phrase is best kept in quotes; while for another search, you may find it is best to allow the words in the phrase be searched apart.
Think about whether or not the phrase you are using needs to be kept together as a search string.
From Basic to Advanced Searching... EBSCOhost
Handout about Boolean searching in EBSCOhost. Use the examples when searching other databases, too.