Perhaps you should try some spelling variations:
thien van » thi van
doanh van » doan van, doanh va, doanh ban
hieu van » hieu va, lieu va, hieu ve
cham tuc » nham thuc, pham thuc, tham thuc
va doanh » van doanh, vay doanh, va danh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
tuc va » thuc va, truc va, tuc xa
van va » van vat, van van, ban va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang cao hoi. ((hieu van) or (thien van)) cham tuc va doanh van va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang cao hoi. ((hieu van) OR (thien van)) cham tuc va doanh van va thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cao hoi. ((hieu van) or (thien van)) cham tuc va doanh van va thiet*.