Perhaps you should try some spelling variations:
dung quang » dang quang, luong quang, dung luan
dung quan » dung luan, luong quan, dang quang
hieu suat » hieu luat, hieu qua
quang ban » quang binh, quang tuan, quang tran
kiem soat » kiem toan
van hieu » cao hieu
dan kiem » van kiem, toan kiem, phan kiem
ban dan » ban hang, ban hanh, ban quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tinh ((dung quan) OR (dung quang)) van hieu suat ) or ( tinh quang ban dan kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh ((dung quan) OR (dung quang)) van hieu suat ) OR ( tinh quang ban dan kiem soat )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tinh ((dung quan) OR (dung quang)) van hieu suat ) or ( tinh quang ban dan kiem soat ))".
• Adding a wildcard symbol may retrieve word variants: (( tinh ((dung quan) OR (dung quang)) van hieu suat ) or ( tinh quang ban dan kiem soat ))*.