Perhaps you should try some spelling variations:
der filosofia » de filosofia, e filosofia, da filosofia
la literature » la litterature, a literature, la literatura
di filosofia » la filosofia, e filosofia
tests drug » test drug, testing drug, tests during

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 studies ((der filosofia) OR (di filosofia)) la literature".
• Adding a wildcard symbol may retrieve word variants: tests drug studies ((der filosofia) OR (di filosofia)) la literature*.