Perhaps you should try some spelling variations:
del literature » model literature, abel literature, fuel literature
studium die » studium der, studium des
studium di » studium i, studium ii, studium d
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 ii ((studium di) OR (studium die)) filosofia del literature".
• Adding a wildcard symbol may retrieve word variants: test ii ((studium di) OR (studium die)) filosofia del literature*.