Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cao quoc » cac quoc, cao thuoc, han quoc
quoc ban » quoc bao, quoc lan, quoc quan
ban hanh » ban hang
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) ky tang xa hoi. lieu va cao quoc ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky tang xa hoi. lieu va cao quoc ban hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky tang xa hoi. lieu va cao quoc ban hanh vi cua tre*.