Perhaps you should try some spelling variations:
doubles studium » duales studium
de litterature » la litterature, et litterature
ds filosofica » di filosofia, da filosofia, e filosofica
de filosofia » e filosofia, di filosofia, la filosofia

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: (test OR text) doubles studium ((ds filosofica) OR (de filosofia)) de litterature.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(test or text) doubles studium ((ds filosofica) OR (de filosofia)) de litterature".
• Adding a wildcard symbol may retrieve word variants: (test or text) doubles studium ((ds filosofica) OR (de filosofia)) de litterature*.