Perhaps you should try some spelling variations:
hieu soat » hieu suat, hieu hoat, hieu luat
dien hoat » dien hoa, dien hat, trien hoat
dung lan » dung luan, dung land, dung lam
van hieu » cao hieu
quang vi » quang si, quang va, quans vi
lan van » luan van, lang van, tan van
quan vi » quan li, quan tri, quan doi
tin » tinh

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

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