Perhaps you should try some spelling variations:
dung tang » dung thang, dung trang, dung dang
hieu luat » hieu qua
tinh nang » trinh nang, tin nang, tich nang
nang quan » ban quan, nang suat
hien soat » thien hoat, kiem soat, bien soan
tang van » dang van, hoang van, trong van
van hieu » cao hieu
quan van » luan van, quan va, quan luan
van hien » van tien

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 tang van hieu luat ) or ( tinh nang quan van hien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung tang van hieu luat ) OR ( tinh nang quan van hien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung tang van hieu luat ) or ( tinh nang quan van hien soat ))*.