Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dang xay » dang van, van xay
ban dang » ban hang, van dang, ban danh
hai cua » thai cua, dai cua, hoi cua
ban dan » ban hang, ban hanh, ban quan
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
dao duc » giao duc, tao duoc
hieu ve » hieu va, hieu van
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky dang xay hoi. hieu ve ((dao duc) or (pham duc)) ((ban dang) or (ban dan)) hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky dang xay hoi. hieu ve ((dao duc) OR (pham duc)) ((ban dang) OR (ban dan)) hai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang xay hoi. hieu ve ((dao duc) or (pham duc)) ((ban dang) or (ban dan)) hai cua tre*.