When searching for books on a particular topic, it is helpful to use Library of Congress subject headings. Here are a few subject headings for finding books on Gothic cathedrals.
Architecture--Gothic
Architecture--Medieval Europe
Art--Gothic
Art--Medieval
Church architecture--France
Glass painting and staining--France
Sculpture--Gothic
You may want to use Scout, the library's discovery search engine, to find many resources at once, including books, articles, and videos.
Here are some tips for getting the most out of Scout:
Use a keyword search to get many results.