Perhaps you should try some spelling variations:
results sample » results example, results simply, results examples
da literatura » la literatura, a literatura, de literatura
sample study » example study
di filosofia » la filosofia
e filosofia » la filosofia

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: results sample study ((e filosofia) OR (di filosofia)) da literatura.
• Adding a wildcard symbol may retrieve word variants: results sample study ((e filosofia) or (di filosofia)) da literatura*.