Perhaps you should try some spelling variations:
stents safety » agents safety, events safety, tenth safety
a literatura » la literatura, a literature, y literatura
studien die » studien der
filosofia a » filosofia da, filosofia la, filosofia e
studie die » studie der

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: "stents safety ((studien die) OR (studie die)) filosofia a literatura".
• Adding a wildcard symbol may retrieve word variants: stents safety ((studien die) OR (studie die)) filosofia a literatura*.