Perhaps you should try some spelling variations:
del literature » model literature, abel literature, fuel literature
studium la » studium a, studium als, studium das
test im » test i, fest im, test iv
test ii » test i

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 im) OR (test ii)) studium la filosofia del literature".
• Adding a wildcard symbol may retrieve word variants: ((test im) OR (test ii)) studium la filosofia del literature*.