FDWM (De Wulf-Mansion Center):
Ancient, Medieval philosophy and renaissance philosophy.
FHIW:
General philosophical collection, encyclopedias, historical overviews, and introductory texts in various domains.
Modern and contemporary philosophy.
FHUA (Husserl archives)
FHUS: Personal library of Husserl, it’s a museum collection. (Not necessarily books by Husserl but books that he personally owned)
FLFW: Logic and philosophy of science
FBIB: Library of HIW generally, also includes inaccessible collection.