Use the Subjects list in the catalog's left column to get the best results.
Here are some good subjects to try:
You can search for books using ChesCat, the library's catalog. Good search terms would include your author's name, the title of the work, or "literary criticism" in general. Try looking for links like "[Your author's name]--Criticism and interpretation" in the Subjects list in the left column; that will give you search results that are only literary criticsm:
You may have to scroll down some to see the Subjects list on the left.