Perhaps you should try some spelling variations:
de litterature » la litterature, et litterature
duale studien » duale studium, scale studien, duales studium
de literatura » la literatura, y literatura, a literatura
es filosofia » e filosofia, em filosofia, la filosofia
studien es » studien aus, studien bei, studien ein
testo » test, tests, texto

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: "testo duale studien es filosofia ((de literatura) OR (de litterature))*".