Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
dau thuc » dan thuc, dai thuc, dam thuc
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
hanh dai » hanh tai, hanh dao, vanh dai
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
van dau » van dao, phan dau
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach thu)) nang ma hoi. hieu van dau thuc dan hanh dai cua tre~.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach thu)) nang ma hoi. hieu van dau thuc dan hanh dai cua tre*.