Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh de » hanh de, thanh ve, thanh do
su sach » vu sach
luc ban » duc ban, cuc ban, luc bat
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
tay hoi » tay ho, tao hoi, tay thai
xay hoi » xa hoi, cay phoi, gay thoi
ky dang » ky nang, ky danh
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
de cua » le cua, te cua, dieu cua

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) OR (so sach)) ky dang ((xay hoi) OR (tay hoi)). hieu ve cac luc ban thanh de cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sach)) ky dang ((xay hoi) OR (tay hoi)). hieu ve cac luc ban thanh de cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky dang ((xay hoi) OR (tay hoi)). hieu ve cac luc ban thanh de cua tre*.