Perhaps you should try some spelling variations:
duale studie » duale studien, duale studium, duales studium
filosofia la » filosofia le, filosofica da, filosofia das
filosofia da » filosofia de, filosofia del, filosofia e
tests duale » tests due, tests scale, tests damage
studie die » studie der

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: tests duale studie die ((filosofia la) OR (filosofia da)) literatura.
• Adding a wildcard symbol may retrieve word variants: tests duale studie die ((filosofia la) or (filosofia da)) literatura*.