Perhaps you should try some spelling variations:
del literatura » de literatura, pela literatura, da literatura
duales studium » das studium
test duales » test doubles, test rules, test oracles
y filosofia » e filosofia, la filosofia, di filosofia
a filosofia » la filosofia, e filosofia, di 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: "test duales studium ((y filosofia) OR (a filosofia)) del literatura".
• Adding a wildcard symbol may retrieve word variants: test duales studium ((y filosofia) OR (a filosofia)) del literatura*.