Perhaps you should try some spelling variations:
ban hanh » ban hang
ky tang » ky nang, ky dang, kho tang
dai hoi » dai hoc, dai hai
dai moi » doi moi
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ve ham » ve cham, le ham, ve am
ham so » nam so, cham soc
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.

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