Perhaps you should try some spelling variations:
duale studien » duale studium, scale studien, duales studium
la literatura » la litterature, a literature
a literatura » a literature, y literatura, a literatur
texto duale » texto durante

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 _ filosofia ((a literatura) OR (la literatura))".
• Adding a wildcard symbol may retrieve word variants: texto duale studien _ filosofia ((a literatura) OR (la literatura))*.