Perhaps you should try some spelling variations:
yanling yang » yang yang, ying yang
der tests » des tests, der trusts, user tests
song rong » song chong, hong song, song bing
der test » der text, per test, der texte
art song » a song
rong yu » hong yu, rong su, wong yue
wang » wing, wan, lang

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

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