If you know the title or author, search for that using the Author Keyword, Title Keyword or Author Title Keyword options.
If you want to find books about Graphic Novels, search on keyword 'graphic novels'.
If you want to find books that ARE graphic novels (genre/format), search for Comics (Graphic works) These are defined by Library of Congress as: "Narrative works that employ sequential art, and often prose, to tell the story". These may be further broken down by genre:
Action and adventure comics
Detective and mystery comics
Sicience fiction comics
If UVic Libraries does not have a book that you need, you may order it via Interlibrary Loan, but first check GVPL's catalogue to make sure it's not available there. GVPL has an extensive collection of graphic novels and books about graphic novels, and these can be sent to any branch library that's convenient to you.