Many databases have a Thesaurus or a Subject Term glossary. These feature a subject specific thesaurus of subject terms that relate to content on those databases. The thesaurus allows you to browse for subject terms you can use to search the database. Subject terms are assigned based on article content, allowing you to create a targeted search.
You can find the Thesaurus or Subject Term Glossary at the top of the search page for the database.
When searching a specific term, type it into the text box, click the button that says "Relevancy Ranked," and click the "Browse" button as seen in the picture to the right.