Perhaps you should try some spelling variations:
done hoang » dong hoang
gene sang » lee sang, gene bank
sang minh » kang minah, anh minh, song min
hoang sy » hoang vu
cong seo » hong seo, cong shu, cong sun
long ago » long arm
a gene » a genre, a gender, a gentle
sy a » y a, my a, si a

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

• Performing a fuzzy search may retrieve terms with similar spellings: done hoang sy a gene sang minh ((cong seo) or (long ago)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: done hoang sy a gene sang minh ((cong seo) OR (long ago)) ;.
• Adding a wildcard symbol may retrieve word variants: done hoang sy a gene sang minh ((cong seo) or (long ago)) ;*.