Perhaps you should try some spelling variations:
hanh lai » hanh lam, hanh tai, thanh lap
tu sach » thu sach, su sach, te sach
truc va » thuc va, thuc vat, trung va
ky tang » ky nang, ky dang, kho tang
dan hoi » dai hoi, van hoi, dang khoi
lai cua » dai cua, hai cua, lai chau
dan hoc » van hoc, dan toc, dai hoc
hieu vu » hieu va, hieu ve, hieu su
sach ky » sac ky, sach y, sach ty
vu cao » cu cao, va cao
tuc va » thuc va, tuc xa, duc va
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 tang ((dan hoi) OR (dan hoc)). hieu vu cao ((tuc va) or (truc va)) hanh lai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang ((dan hoi) OR (dan hoc)). hieu vu cao ((tuc va) OR (truc va)) hanh lai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky tang ((dan hoi) OR (dan hoc)). hieu vu cao ((tuc va) or (truc va)) hanh lai cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang ((dan hoi) OR (dan hoc)). hieu vu cao ((tuc va) or (truc va)) hanh lai cua te*.