Perhaps you should try some spelling variations:
stents safety » agents safety, events safety, tenth safety
die filosofia » di filosofia, de filosofia, e filosofia
a literatura » la literatura, a literature, a literatur
y literatura » la literatura
studies die » studie die, studien die, studies does

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