Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
van hanh » van thanh, ban hanh, van anh
sach vu » sach va, sach tu, sach uu
va tinh » may tinh
cam luc » cam xuc, cau luc
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
vu nang » vuc nang, va nang, vu dang
cua tre » cua te, cuu tre, cua triet
ca cua » co cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach vu nang xa hoi. ((hieu va) or (lieu va)) cam luc ((van hanh) or (va tinh)) ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach vu nang xa hoi. ((hieu va) OR (lieu va)) cam luc ((van hanh) OR (va tinh)) ca cua tre.
• Adding a wildcard symbol may retrieve word variants: hoc sach vu nang xa hoi. ((hieu va) or (lieu va)) cam luc ((van hanh) or (va tinh)) ca cua tre*.