Perhaps you should try some spelling variations:
filosofica da » filosofia da, filosofia de, filosofia di
items studie » stems studies, items die, cems studies
filosofia la » filosofia da, filosofia le, filosofia das
test items » test systems
studie der » studium 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: test items studie der ((filosofia la) OR (filosofica da)) literatura.
• Adding a wildcard symbol may retrieve word variants: test items studie der ((filosofia la) or (filosofica da)) literatura*.