Did you know that in addition to using a keyword search to find material you can also use a subject heading search to find material that a keyword search might miss?
Once you find an book that looks promising, check the subject headings that the item is tagged with. Click on the subject heading and proceed to find all the material in the catalog with that subject heading.
After you learn some subject headings, try doing a Subject Keywords search instead of the normal Keywords Anywhere search.
You can also use subject searches when searching for articles in databases. You can even combine keyword and subject searches in one query to get very focused results.