In the Library's catalog, you can use keywords or Library of Congress subject headings to locate relevant books of interest on your topic.
Use truncation or wildcards (* or ?) for variations of words (e.g. vatican*) to begin a keyword search and use subject headings like these below to explore further in your search:
Browsing physically or virtually in call number ranges is another path towards discovery. If you search OskiCat by these LC call numbers, you can generate clean lists of comics and graphic novels by country of publication: