Perhaps you should try some spelling variations:
a literatura » la literatura, a literature, y literatura
test duales » test doubles, test oracles, test dummies
filosofia a » filosofia da, filosofia la, filosofia e
test rules » best rules, test rule, trust rules

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: "((test duales) OR (test rules)) studium _ filosofia a literatura*".