Perhaps you should try some spelling variations:
dong hoang » hong hong
than daun » than bau, than daem, than data
yang mind » yang cindy, yang jin, tang min
sang minh » kang minah, anh minh, song min
hoang ka » hoang vu, hoang sy, hoang _
can data » can tata, dan data, fan data
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 hoang ka ((than daun) OR (can data)) ((yang mind) OR (sang minh)) how ai ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dong hoang ka ((than daun) or (can data)) ((yang mind) OR (sang minh)) how ai ;~".
• Adding a wildcard symbol may retrieve word variants: dong hoang ka ((than daun) or (can data)) ((yang mind) OR (sang minh)) how ai ;*.