Perhaps you should try some spelling variations:
der filosofia » de filosofia, e filosofia, di filosofia
le literatura » la literatura, de literatura, e literatura
filosofia le » filosofia de, filosofia e, filosofia del
de estudio » de estudios, un estudio, de estado
de studio » _ studio, a studio, im studio

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: "tests ((de studio) OR (de estudio)) der filosofia le literatura".
• Adding a wildcard symbol may retrieve word variants: tests ((de studio) OR (de estudio)) der filosofia le literatura*.