Perhaps you should try some spelling variations:
khong cong » thong cong, khong cang, chong cong
hoac khong » hoa khong, hoc khong, hay khong
phan tien » phan kien, phan bien, phap tieng
tang hoac » trang hoat, hang hoa, nang hoc
pho bien » phan bien, che bien
anh tang » anh bang, anh dang, anh nang
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan ban » van ban
so bien » mot bien

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((pho bien) or (phan tien))) or (so bien)) tinh - anh tang hoac khong cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((pho bien) OR (phan tien))) OR (so bien)) tinh - anh tang hoac khong cong san toan ban.
• Adding a wildcard symbol may retrieve word variants: ((((pho bien) or (phan tien))) or (so bien)) tinh - anh tang hoac khong cong san toan ban*.