Books are shelved on the second and third floors of the library, and are organized by Library of Congress call numbers. These call numbers are associated with certain subjects, so related books will be shelved closer together. Once you find a book that matches your research needs, try browsing in that same section to find more relevant books.
Here are some useful call number ranges and their associated subjects:
NK1700-2195 Interior Decoration
NK2200-2750 Furniture