Perhaps you should try some spelling variations:
ban hanh » ban hang
ky tang » ky nang, ky dang, kho tang
mai hoi » mai khoi, dai hoi, mai doi
lai hoi » dai hoi, lai hoa, lai roi
hieu va » lieu va, hieu qua
va cham » va chat, va tham
cham so » cham soc, cham o, ham so
cua tre » cua te, cuu tre, cua triet
so ban » sao ban, so bang, co ban
vi cua » vai cua, di cua

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: tu cac ky tang ((le hoi) OR (((mai hoi) OR (lai hoi)))). hieu va cham so ban hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky tang ((le hoi) or (((mai hoi) OR (lai hoi)))). hieu va cham so ban hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang ((le hoi) or (((mai hoi) OR (lai hoi)))). hieu va cham so ban hanh vi cua tre*.