Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh dai » hanh tai, hanh dao, vanh dai
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cai
va cao » va cac, va co, va dao
tuc va » thuc va, truc va, tuc xa

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 ky tang xa hoi. hieu ((va cam) or (va cao)) tuc va hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky tang xa hoi. hieu ((va cam) OR (va cao)) tuc va hanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky tang xa hoi. hieu ((va cam) or (va cao)) tuc va hanh dai cua tre*.