Perhaps you should try some spelling variations:
der filosofia » de filosofia, e filosofia, di filosofia
la literatura » la litterature
des studie » des studien, desi studie, aes studies
studie der » studium der
tests des » test des, tests der, tests test

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 des studie der filosofia ((la literatura) OR (a literature))".
• Adding a wildcard symbol may retrieve word variants: tests des studie der filosofia ((la literatura) OR (a literature))*.