Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hoc bang » hoc bong, hoc tang, hoc dan
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu va
soc ban » hoc ban, coc ban, so ban
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
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 ma hoi. ((hieu ve) OR (hieu van)) cham ((soc ban) OR (hoc bang)) hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky tang ma hoi. ((hieu ve) OR (hieu van)) cham ((soc ban) or (hoc bang)) hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang ma hoi. ((hieu ve) OR (hieu van)) cham ((soc ban) or (hoc bang)) hanh vi cua tre*.