Perhaps you should try some spelling variations:
ban thanh » ban hanh
ban hang » ngan hang
su sach » vu sach
cac luc » cau luc, coc luc, cac nuoc
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
so sach » so sanh, bo sach, co sach
de cua » le cua, te cua, dieu cua
ve cac » va cac, vien cac

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