Perhaps you should try some spelling variations:
de literatura » de litterature, la literatura, a literatura
y literatura » la literatura
studium als » studium des
studium la » studium a, studium das, studium _
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 la) OR (studium als)) filosofia ((de literatura) OR (y literatura)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "text des ((studium la) OR (studium als)) filosofia ((de literatura) or (y literatura))".
• Adding a wildcard symbol may retrieve word variants: text des ((studium la) OR (studium als)) filosofia ((de literatura) or (y literatura))*.