Perhaps you should try some spelling variations:
dung quang » dang quang, dung quan, luong quang
quang cao » nang cao, quang nam
hieu soat » hieu suat, hieu hoat, hieu luat
tinh dang » tinh dung, binh dang, tinh sang
dang quan » dang quang, nang quan, dung quan
tien soat » trien hoat, thien hoat, tien hoa
kiem soat » kiem toan
quan van » luan van, quan va, quan luan

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: (( trinh dung quang cao hieu soat ) OR ( tinh dang quan van ((tien soat) OR (kiem soat)) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( trinh dung quang cao hieu soat ) or ( tinh dang quan van ((tien soat) OR (kiem soat)) ))~".
• Adding a wildcard symbol may retrieve word variants: (( trinh dung quang cao hieu soat ) or ( tinh dang quan van ((tien soat) OR (kiem soat)) ))*.