Perhaps you should try some spelling variations:
1 filosofica » e filosofica, a filosofia, y filosofia
drug studie » drug studies, drugs studies, drugs studied
e filosofia » la filosofia
tests drug » test drug, testing drug, tests during
literatur » literature

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "tests drug studie ((1 filosofica) OR (e filosofia)) e literatur".
• Adding a wildcard symbol may retrieve word variants: tests drug studie ((1 filosofica) OR (e filosofia)) e literatur*.