Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vai » thanh hai, thanh van, thanh tai
hieu van » thien van, lieu va, hieu ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
cay cua » ca cua, day cua, cay ca
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, me hoi

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) or (ma hoa)). ((hieu van) OR (hieu va)) cay cua ban thanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((ma hoi) OR (ma hoa)). ((hieu van) OR (hieu va)) cay cua ban thanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ((ma hoi) or (ma hoa)). ((hieu van) OR (hieu va)) cay cua ban thanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((ma hoi) or (ma hoa)). ((hieu van) OR (hieu va)) cay cua ban thanh vai cuu tre*.