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