Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
xa vinh » xa sinh, xa tinh, van vinh
xa vanh » xa van, xa thanh, xa khanh
cao duc » dao duc, cao suc, giao duc
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
cong xa » cong xay, cong xua, cong ha
tu cong » thu cong, te cong, tai cong
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: ((te sach) OR (toc sach)) tu cong xa hoi. hieu va cao duc ((xa vanh) OR (xa vinh)) dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) tu cong xa hoi. hieu va cao duc ((xa vanh) OR (xa vinh)) dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) tu cong xa hoi. hieu va cao duc ((xa vanh) OR (xa vinh)) dai cua tre*.