Perhaps you should try some spelling variations:
la literatura » la litterature, a literature
die filosofia » di filosofia, de filosofia, e filosofia
filosofia la » filosofia da, filosofia le, filosofica da
tests drug » testing drug, tests during
studie die » studie der
test drug » best drugs, test du, fast drug

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) OR (test drug)) studie die filosofia la literatura".
• Adding a wildcard symbol may retrieve word variants: ((tests drug) OR (test drug)) studie die filosofia la literatura*.