Perhaps you should try some spelling variations:
yang guang » yan guan, yang liang
than china » tuan china, han china, wuhan china
yao longer » a longer
yang yang » wang yang, wang yan
hui yang » hui ying, du yang, h yang
yang yao » wang yan, yang yi, yang fan
longer a » longer _

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((yang yang) or (yang guang)) ((yuan fei) or (than china)) hui yang yao longer a ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((yang yang) OR (yang guang)) ((yuan fei) OR (than china)) hui yang yao longer a ;.
• Adding a wildcard symbol may retrieve word variants: ((yang yang) or (yang guang)) ((yuan fei) or (than china)) hui yang yao longer a ;*.