Perhaps you should try some spelling variations:
yang cindy » yang mind
hoang yao » gang yao
cindy how » mind how, city how
yang yao » yang yang, wang yan, yang yi
than bau » than bad, than a, than you
can data » can tata, dan data, fan data
how hai » how has, how ai, how hci

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