Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vai » thanh hai, thanh van, thanh tai
nam quoc » nam duoc, nam buoc, nam thuoc
quoc ban » quoc bao, quoc lan, quoc quan
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
va nam » van nam, ha nam, va nay
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (cac ky)) nang x hoi. hieu va nam quoc ban thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (cac ky)) nang x hoi. hieu va nam quoc ban thanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (cac ky)) nang x hoi. hieu va nam quoc ban thanh vai cua tre*.