Perhaps you should try some spelling variations:
days studium » als studium, des studium, duales studium
da filosofia » la filosofia, a filosofia, de filosofia
di filosofia » la filosofia, e filosofia
literatur » literature

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: best ((days studium) OR (das studium)) ((da filosofia) OR (di filosofia)) e literatur.
• The words AND, OR and NOT may confuse the search; try adding quotes: "best ((days studium) OR (das studium)) ((da filosofia) or (di filosofia)) e literatur".
• Adding a wildcard symbol may retrieve word variants: best ((days studium) OR (das studium)) ((da filosofia) or (di filosofia)) e literatur*.