Perhaps you should try some spelling variations:
duale studien » duale studium, scale studien, duales studium
e literatura » de literatura, y literatura, a literatura
tests duale » tests due, tests scale, tests damage
literatura » literaturea
literatur » literature

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: "tests duale studien _ filosofia ((e literatura) OR (e literatur))*".