Perhaps you should try some spelling variations:
de litterature » la litterature, et litterature
duales studium » das studium
tests duales » tests dalekjs, tests des, neues duales
di filosofia » la filosofia, e filosofia
y literatura » la literatura
studium di » studium die, studium i, studium ii

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: tests duales studium di filosofia ((y literatura) OR (de litterature))*.