Perhaps you should try some spelling variations:
lang ying » liang ying, huang ying, zhang ying
ying yang » yang yang, yin yang, ying chang
per test » der tests, per cent, asr test
der test » der tests, der text, der texte
art song » a song
jeong su » jeong _, jeong mi, jeong 情
rong su » rong yu, cong sun, yong suk

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

• Performing a fuzzy search may retrieve terms with similar spellings: lang ying yang ((per test) or (der test)) art song ((rong su) OR (jeong su)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: lang ying yang ((per test) OR (der test)) art song ((rong su) OR (jeong su)) ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "lang ying yang ((per test) or (der test)) art song ((rong su) OR (jeong su)) ;".
• Adding a wildcard symbol may retrieve word variants: lang ying yang ((per test) or (der test)) art song ((rong su) OR (jeong su)) ;*.