Perhaps you should try some spelling variations:
ban hanh » ban hang
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cao xuc » cam xuc, cao duc, cao suc
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang co » nang doc, nang noi, nang hoc
va cao » va cac, va co, va dao

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu ((nang co) OR (nang cao)) hoi. hieu va cao xuc ((va hanh) OR (ban hanh)) vai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach tu ((nang co) OR (nang cao)) hoi. hieu va cao xuc ((va hanh) or (ban hanh)) vai cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach tu ((nang co) OR (nang cao)) hoi. hieu va cao xuc ((va hanh) or (ban hanh)) vai cua tre*.