Perhaps you should try some spelling variations:
mai khoi » mai khoa, tai khoa, cac khoi
ban hang » ngan hang
ky tang » ky nang, ky dang, kho tang
mai hoi » dai hoi, lai hoi, mai doi
hieu va » lieu va, hieu qua
va cham » va chat, va tham
cham so » cham soc, cham o, ham so
hang vi » hang va, hanh vi, hang di
cua tre » cua te, cuu tre, cua triet
me hoi » le hoi
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 ((me hoi) OR (((mai hoi) OR (mai khoi)))). hieu va cham so ban hang vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky tang ((me hoi) or (((mai hoi) OR (mai khoi)))). hieu va cham so ban hang vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang ((me hoi) or (((mai hoi) OR (mai khoi)))). hieu va cham so ban hang vi cua tre*.