Perhaps you should try some spelling variations:
la litterature » a literature
stents safety » agents safety, events safety, tests safety
tenth safety » heath safety, kent safety, ninth safety
filosofia la » filosofia da, filosofia le, filosofica da
a filosofia » la filosofia, e filosofia, di filosofia
studien a » studien am, studien _, studien 3

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: ((stents safety) OR (tenth safety)) studien a filosofia la litterature*.