Perhaps you should try some spelling variations:
tinh khong » tinh khang, tinh huong, benh khong
quang quan » quang tuan, quang uan, quan quan
hieu soat » hieu suat, hieu hoat, hieu luat
tien soat » trien hoat, thien hoat, kiem soat
quan van » luan van, quan luan, quan doan
quan vi » quan li, quan tri, quan doi
vi hieu » vi dieu, va hieu, vo hieu
quan va » quan ha, luan va, quan ve

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 quan vi hieu soat ) or ( tinh khong ((quan van) or (quan va)) tien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh quang quan vi hieu soat ) OR ( tinh khong ((quan van) OR (quan va)) tien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh quang quan vi hieu soat ) or ( tinh khong ((quan van) or (quan va)) tien soat ))*.