Perhaps you should try some spelling variations:
en literatura » e literatura, pena literatura, en litterature
filosofia en » filosofia e, filosofia del, filosofia con
studium 3 » studium _, studium 8, studium im
studium 1 » studium _, studium 8, studium im
text das » text des, text data, text 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: text das ((studium 3) OR (studium 1)) filosofia en literatura.
• Adding a wildcard symbol may retrieve word variants: text das ((studium 3) or (studium 1)) filosofia en literatura*.