Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh dai » hanh tai, hanh dao, vanh dai
nam thuc » nam thuoc, am thuc, nam thu
dai cuu » dai cua, dai huu
va hanh » van hanh, va thanh, va danh
sach tu » sach thu, cach tu, sach ty
hieu ve » hieu va, hieu van
mang xa » mang may, dang xay, mang cua
lang xa » lang ha, dang xay, lang van
cuu tre » cua tre, cau tren, cau treo
cam tu » cam thu, nam tu, dam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tu ((mang xa) or (lang xa)) hoi. hieu ve ((nam thuc) or (cam tu)) va hanh dai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tu ((mang xa) OR (lang xa)) hoi. hieu ve ((nam thuc) OR (cam tu)) va hanh dai cuu tre.
• Adding a wildcard symbol may retrieve word variants: toc sach tu ((mang xa) or (lang xa)) hoi. hieu ve ((nam thuc) or (cam tu)) va hanh dai cuu tre*.