Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
nam mua » nam cua, nam qua, nam xua
hai cua » thai cua, dai cua, hoi cua
lai cua » dai cua, lai chau, thai cua
mua ban » cua ban, qua ban
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
hieu ve » hieu van
nang ma » tang ma, sang ma, nang 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 ky nang ma hoi. ((hieu ve) or (hieu va)) nam mua ban thanh ((lai cua) OR (hai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. ((hieu ve) OR (hieu va)) nam mua ban thanh ((lai cua) OR (hai cua)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ma hoi. ((hieu ve) or (hieu va)) nam mua ban thanh ((lai cua) OR (hai cua)) triet*".