Department library (Library of the Department of South Slavonic and Balkan Studies) is part of the Central Library of the Faculty of Arts:
This link leads you to Charles University Central Catalogue which allows you to search in all libraries of the university.
Reference libraries on KJBS department:
Albanian Studies Library – room n. 309A (contact person Dr. O. Backus Borshi)
Romanian Studies Library – room n. 301 Hybernská (contact person PhDr. J. Našinec)