Perhaps you should try some spelling variations:
le literatura » la literatura, de literatura, e literatura
da filosofia » la filosofia, a filosofia, de filosofia
di filosofia » la filosofia, e filosofia
de studium » dem studium, des studium, d 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: "est de studium ((da filosofia) OR (di filosofia)) le literatura".
• Adding a wildcard symbol may retrieve word variants: est de studium ((da filosofia) OR (di filosofia)) le literatura*.