Perhaps you should try some spelling variations:
lang yanling » wang yanling, wang yangming, zhang yunling
yanling yang » yang yang, ying yang
der test » der tests, der text, der texte
per test » der tests, per cent, asr test
jin song » john song, kim song, jin ying
jie song » jae song, kim song, li song
cong sun » cong shu, cong van, wing sun

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: lang yanling yang ((der test) or (per test)) ((jin song) or (jie song)) cong sun ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: lang yanling yang ((der test) OR (per test)) ((jin song) OR (jie song)) cong sun ;.
• Adding a wildcard symbol may retrieve word variants: lang yanling yang ((der test) or (per test)) ((jin song) or (jie song)) cong sun ;*.