Perhaps you should try some spelling variations:
yong hoang » dong hoang, hong hong, kong hang
wang yong » wang yang, wang hyoung, wang yan
yang yang » wang yang, wang yan
shang hai » shang kai, dang hai, chang ha
hoang sy » hoang vu
wong yue » wang yue, hong yu
yang li » yang lin, yang di, yang xi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: wang yong hoang sy ((yang yang) OR (yang li)) yi ((shang hai) OR (wong yue)) ;~.
• Adding a wildcard symbol may retrieve word variants: wang yong hoang sy ((yang yang) or (yang li)) yi ((shang hai) or (wong yue)) ;*.