Perhaps you should try some spelling variations:
del literatur » model literatur, teil literatur, igel literatur
studium la » studium a, studium als, studium das
test day » test data, feast day, fast day
rest day » great day, feast day, rest data

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 day) OR (rest day)) studium la filosofia del literatur*".