Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu qua, diep quang
thanh hang » thanh hoang, thanh thang, tranh hang
hieu quan » hieu qua, lieu quan, thien quan
tong cong » trong cong, cong cong, dung cong
thanh cac » hanh cac, thanh bac, thanh ca
cong ban » cong bang, cong san, cong tan
than cap » khan cap, thanh lap, than cua
va tong » va thong, va tuong, va trong

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu quang) or (hieu quan)) - thanh hang va tong cong ban ((than cap) or (thanh cac))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu quang) OR (hieu quan)) - thanh hang va tong cong ban ((than cap) OR (thanh cac))*.