Perhaps you should try some spelling variations:
quang lam » quang nam, dung lam, quang le
quang cao » nang cao, quang nam
hieu suat » hieu luat, hieu qua
tien soat » trien hoat, thien hoat, kiem soat
van hieu » cao hieu
van tien » toan tien, van tuan
tinh » trinh, dinh, minh
luan » quan, lan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tinh ((quang lam) or (quang cao)) van hieu suat ) or ( tin dung luan van tien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh ((quang lam) OR (quang cao)) van hieu suat ) OR ( tin dung luan van tien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh ((quang lam) or (quang cao)) van hieu suat ) or ( tin dung luan van tien soat ))*.