Perhaps you should try some spelling variations:
dong yang » dong hoang, wang yang, yang yang
than daun » than bau, than daem, than data
yang yao » yang yang, wang yan, yang yi
can data » can tata, dan data, fan data
yang jun » yang jui, pang jun, yang jin
how hai » how ai, how hci, how have
how has » how have

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 yao ((than daun) OR (can data)) yang jun ((how hai) OR (how has)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dong yang yao ((than daun) or (can data)) yang jun ((how hai) OR (how has)) ;~".
• Adding a wildcard symbol may retrieve word variants: dong yang yao ((than daun) or (can data)) yang jun ((how hai) OR (how has)) ;*.