Perhaps you should try some spelling variations:
change timor » change time, change theory, change timing
chen change » when change, chen changyue, chain change
yang yang » wang yang, wang yan
hua chen » jui chen, yu chen, a chen
wang hui » wang hua, wang zhi, wang wei
yan yan » yan yuan, nan yan, wang yan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (wang or lang) ((yan yan) or (yang yang)) hua chen change timor wang hui ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (wang OR lang) ((yan yan) OR (yang yang)) hua chen change timor wang hui ;.
• Adding a wildcard symbol may retrieve word variants: (wang or lang) ((yan yan) or (yang yang)) hua chen change timor wang hui ;*.