Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
te sach » toc sach
ty nang » ty xang, ty hang, ly nang
van cau » van dau, van hau, van chat
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
co hai » co dai, co hoi, o hai
cau so » cau do, cau o, cao so
so van » su van, vo van

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ty nang) or (ky nang)) co hai. hieu van cau so van hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ky nang)) co hai. hieu van cau so van hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ((ty nang) or (ky nang)) co hai. hieu van cau so van hanh vai cua tre*.