Perhaps you should try some spelling variations:
juan rene » juan meng, juan rana
sang minh » kang minah, anh minh, song min
yan yong » yan cong, wang yong, yang yang
tan yong » tan hong, tan kong, tan yang
tang min » chang min, yang mind, tang li
wong yue » wang yue, hong yu
wang » wing, wan, lang

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 ((yan yong) OR (tan yong)) juan rene ((tang min) OR (sang minh)) wong yue ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((yan yong) OR (tan yong)) juan rene ((tang min) or (sang minh)) wong yue ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((yan yong) OR (tan yong)) juan rene ((tang min) or (sang minh)) wong yue ;*.