Perhaps you should try some spelling variations:
a litterature » la litterature, a literature, _ litterature
studium das » studium des, studium der, studium als
studium die » studium der, studium des
filosofia a » filosofia da, filosofia la, filosofia e
test do » test de, test d, test der

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: "test do ((studium das) OR (studium die)) filosofia a litterature".
• Adding a wildcard symbol may retrieve word variants: test do ((studium das) OR (studium die)) filosofia a litterature*.