Perhaps you should try some spelling variations:
hang vai » hang va, hang tai, hang hai
ban hang » ngan hang
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cay dua » chay dua, cay lua, ca dua
cuu tre » cau tren, cau treo
dua ban » dia ban, cua ban, qua ban
van cay » van cau, van bay, van ca
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cua triet, dua tren
ma hoi » xa hoi, ma hoa, 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: tu sach ky nang ((ma hoi) OR (mai hoi)). hieu van cay dua ban hang vai ((cuu tre) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((ma hoi) OR (mai hoi)). hieu van cay dua ban hang vai ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((ma hoi) OR (mai hoi)). hieu van cay dua ban hang vai ((cuu tre) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((ma hoi) OR (mai hoi)). hieu van cay dua ban hang vai ((cuu tre) or (cua tre))*.