Your topic itself may prove to be the words that may up your search term(s).
Keywords searches look for that search term(s) in the title, subject, author, summary or abstract fields.
Keywords will also be searched for repetition in the document. Keywords found frequently or throughout an article may push that article higher in the search results.
Keywords matches to dot distinguish between context and purpose. It may match the correct word but not in the
A subject search will locate materials by Library of Congress Subject Headings, which is a controlled vocabulary or standard list of subject terms. The University Library assigns Library of Congress Subject Headings to all items listed in the online catalog.
The number of results may vary widely. Some searches will retrieve hundreds of results but if you choose a nonexistent subject term while others get nothing.
If you do not know the appropriate subject heading for your topic, conduct a keyword search first and look at the subject heading(s) for relevant items.