Perhaps you should try some spelling variations:
da literature » a literature, da literatura, la literature
di filosofia » la filosofia, e filosofia
de filosofia » e filosofia, la filosofia, a filosofia
4d studie » 1 studie, 3 studie, 6 studie
4 studie » 4 studies, 1 studie, 3 studie

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 ((4d studie) OR (4 studie)) ((de filosofia) OR (di filosofia)) da literature.
• The words AND, OR and NOT may confuse the search; try adding quotes: "test ((4d studie) OR (4 studie)) ((de filosofia) or (di filosofia)) da literature".
• Adding a wildcard symbol may retrieve word variants: test ((4d studie) OR (4 studie)) ((de filosofia) or (di filosofia)) da literature*.