Perhaps you should try some spelling variations:
hieu soat » hieu hoat, hieu luat, kiem soat
hieu suat » hieu luat, hieu qua
bien soan » bien so
ban quan » van quan
tin ban » tin bat, tim ban, tinh bang
quan va » quan vi, quan ha, luan va
va bien » vat bien, va lien, va dien
luan » lan

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

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