Perhaps you should try some spelling variations:
thien hoat » trien hoat, thien thuat, tien hoa
tich nang » tich van, tin nang
hieu hoat » hieu hoa, hieu luat, hieu suat
nang quan » ban quan, nang suat
dung thi » dung tai, dung tri, dung chi
van hieu » cao hieu
va thien » van thien, va thiet, va trien
thi van » thi lan, thi hanh, thi nang
quan va » quan vi, quan ha, luan va
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 thi van hieu hoat ) or ( tich nang quan va thien hoat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung thi van hieu hoat ) OR ( tich nang quan va thien hoat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung thi van hieu hoat ) or ( tich nang quan va thien hoat ))*.