Perhaps you should try some spelling variations:
del literatura » de literatura, pela literatura, da literatura
duale studien » duale studium, scale studien, duales studium
di filosofia » la filosofia, e filosofia
texto duale » texto durante
a filosofia » la filosofia, e filosofia

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: "texto duale studien ((a filosofia) OR (di filosofia)) del literatura*".