Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cham tuc » nham thuc, pham thuc, tham thuc
van hanh » van thanh, ban hanh, van anh
hieu va » lieu va, hieu qua
va cham » va chat, va tham
tuc van » thuc van, truc van, tuc va
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua
x hoi » xa hoi, o hoi, x ho

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: ((te sach) OR (toc sach)) ky nang x hoi. hieu va cham tuc van hanh di cua tre~.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang x hoi. hieu va cham tuc van hanh di cua tre*.