Perhaps you should try some spelling variations:
das filosofia » da filosofia, la filosofia, di filosofia
de literatura » de litterature, la literatura, a literatura
y literatura » la literatura
des studium » des studiums, das studium, dem studium
studium das » studium des, studium der, studium die
text des » text der

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

• If you are trying to use Boolean operators, they must be ALL CAPS: text des studium das filosofia ((de literatura) OR (y literatura)).
• Adding a wildcard symbol may retrieve word variants: text des studium das filosofia ((de literatura) or (y literatura))*.