Perhaps you should try some spelling variations:
thieu nien » thien nhien
van hanh » van thanh, ban hanh, van anh
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
nien cac » vien cac, dien cac, bien cac
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
tay hoi » tay ho, tao hoi, tay thai
xay hoi » xa hoi, cay phoi, gay thoi
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
va dan » ca dan, va dao, va dau

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 ky dang ((xay hoi) or (tay hoi)). thieu nien cac nuoc ((van hanh) or (va dan)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang ((xay hoi) OR (tay hoi)). thieu nien cac nuoc ((van hanh) OR (va dan)) dai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang ((xay hoi) or (tay hoi)). thieu nien cac nuoc ((van hanh) or (va dan)) dai cua tre*.