Perhaps you should try some spelling variations:
ban thanh » ban hanh
ban hang » ngan hang
su sach » vu sach
san cua » sang cua, ban cua, dan cua
cam dia » cac dia, cam gia, pham dia
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
tu nang » tru nang, tu nong, tu nano
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (so sach)) tu nang ma hoi. hieu va cam dia ((ban thanh) or (ban hang)) san cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) tu nang ma hoi. hieu va cam dia ((ban thanh) OR (ban hang)) san cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) tu nang ma hoi. hieu va cam dia ((ban thanh) or (ban hang)) san cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (so sach)) tu nang ma hoi. hieu va cam dia ((ban thanh) or (ban hang)) san cua tre*.