Perhaps you should try some spelling variations:
duale studien » duale studium, scale studien, duales studium
der filosofia » de filosofia, e filosofia, di filosofia
da literatura » la literatura, de literatura, na literatura
a literatura » la literatura, a literature, y literatura
studien der » studie der, studenten der

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (testo OR texto) duale studien der filosofia ((da literatura) OR (a literatura)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(testo or texto) duale studien der filosofia ((da literatura) OR (a literatura))".
• Adding a wildcard symbol may retrieve word variants: (testo or texto) duale studien der filosofia ((da literatura) OR (a literatura))*.