Results include both print and ebooks, available from Portland State Library and the Summit Libraries.
After you find a useful book in the library catalog, scroll down to the "Details" tab to the book's "Subjects." Here you'll find a list of related subjects that you might consider adding to your search. You can also click on a subject link in the record; clicking on a subject such as "Older people -- Care" would bring up a list of all the Library's books, journals, and other resources on that topic.
Sometimes browsing the library stacks can help you find books you didn't even know you were looking for. The following are good areas to peruse.
Maps of the library are available at the 2nd floor Reference Desk, elevator lobbies, and also online.