Perhaps you should try some spelling variations:
dua tren » dung tren
hang tai » hang va, dung tai
hanh lai » hanh lam, hanh tai, thanh lap
cham tuc » nham thuc, pham thuc, tham thuc
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
tai hoi » tai khoi, dai hoi, tai hai
ky hang » ky nang, ly hang, ky dang
tuc va » thuc va, truc va, tuc xa
cua te » cua tu

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 hang tai hoi. ((hieu ve) OR (hieu va)) cham tuc va hanh lai ((dua tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky hang tai hoi. ((hieu ve) OR (hieu va)) cham tuc va hanh lai ((dua tren) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky hang tai hoi. ((hieu ve) OR (hieu va)) cham tuc va hanh lai ((dua tren) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky hang tai hoi. ((hieu ve) OR (hieu va)) cham tuc va hanh lai ((dua tren) or (cua te))*.