Perhaps you should try some spelling variations:
da literatura » la literatura, a literatura, de literatura
di filosofia » la filosofia, e filosofia
filosofia da » filosofia de, filosofia del, filosofia e
tests scale » tests stable, sets scale, tests safe
test scale » best scale, rest scale, treat scale
studies di » studies die, studies div, studies ds

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: ((test scale) OR (tests scale)) studies di filosofia da literatura.
• Adding a wildcard symbol may retrieve word variants: ((test scale) or (tests scale)) studies di filosofia da literatura*.