Perhaps you should try some spelling variations:
na literatura » la literatura, a literatura, a literature
di filosofia » la filosofia, e filosofia
filosofia na » filosofia da, filosofia la, filosofia n
des studium » des studiums, dem studium, dein studium

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: "text ((des studium) OR (das studium)) di filosofia na literatura*".