Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
hoc sach » hoc sinh, hoc cac, hoc anh
vat hanh » vat thanh, van hanh, va hanh
hanh lai » hanh lam, hanh tai, thanh lap
su sach » so sach, vu sach
te sach » toc sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (((te sach) or (hoc sach)))) ky nang xa hoi. hieu ve cham thuc vat hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (((te sach) OR (hoc sach)))) ky nang xa hoi. hieu ve cham thuc vat hanh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (((te sach) or (hoc sach)))) ky nang xa hoi. hieu ve cham thuc vat hanh lai cua tre*.