Perhaps you should try some spelling variations:
dong yang » dong hoang, wang yang, yang yang
than data » than death, loan data, can data
sang minh » kang minah, anh minh, song min
yang yao » yang yang, wang yan, yang yi
than bau » than bad, than a, than you
minh hoa » mind how
hoa ai » how ai

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

• Performing a fuzzy search may retrieve terms with similar spellings: dong yang yao ((than bau) or (than data)) sang minh hoa ai ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: dong yang yao ((than bau) OR (than data)) sang minh hoa ai ;*.