Perhaps you should try some spelling variations:
stable studien » stadler studien, scale studien, table studies
de filosofica » e filosofica, e filosofia, di filosofia
da literatura » la literatura, a literatura, de literatura
tests stable » tests table, sets stable, test table
de filosofia » e filosofia, di filosofia, la filosofia

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 stable studien ((de filosofica) OR (de filosofia)) da literatura".
• Adding a wildcard symbol may retrieve word variants: tests stable studien ((de filosofica) OR (de filosofia)) da literatura*.