Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
van cac » van hac, van cau, van bac
cac toc » cac toi, cac nuoc, cac thoi
toc van » hoc van, toc san, tac van
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu
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: vu sach ky nang x hoi. hieu van cac toc van hanh vi ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang x hoi. hieu van cac toc van hanh vi ((cua tre) OR (cua te))*.