Perhaps you should try some spelling variations:
quang luan » quan luan, quang tuan, quang uan
minh thong » minh thuong, minh tuong, minh thang
hieu suat » hieu luat, hieu qua
lien soat » bien soan, lien son, dien hoat
kiem soat » kiem toan
van hieu » cao hieu
tinh » trinh, dinh, kinh

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: (( tinh quang luan van hieu suat ) OR ( minh thong quan tri ((lien soat) OR (kiem soat)) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tinh quang luan van hieu suat ) or ( minh thong quan tri ((lien soat) OR (kiem soat)) ))~".
• Adding a wildcard symbol may retrieve word variants: (( tinh quang luan van hieu suat ) or ( minh thong quan tri ((lien soat) OR (kiem soat)) ))*.