Perhaps you should try some spelling variations:
dong yang » dong hoang, wang yang, yang yang
than data » than death, loan data, can data
yang mind » yang cindy, yang jin, tang min
sang minh » kang minah, anh minh, song min
than bad » than bau, than a, than big
yang ka » yang fan, yang yao
how ai » how aid, how ae, how am

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: dong yang ka ((than bad) OR (than data)) ((yang mind) OR (sang minh)) how ai ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dong yang ka ((than bad) or (than data)) ((yang mind) OR (sang minh)) how ai ;~".
• Adding a wildcard symbol may retrieve word variants: dong yang ka ((than bad) or (than data)) ((yang mind) OR (sang minh)) how ai ;*.