Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cuu tre, cua triet
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu va
vi cua » vai cua, di cua
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ky tang ma hoi. ((hieu ve) or (hieu van)) ((pham duc) or (cham soc)) van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky tang ma hoi. ((hieu ve) OR (hieu van)) ((pham duc) OR (cham soc)) van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu san ky tang ma hoi. ((hieu ve) or (hieu van)) ((pham duc) or (cham soc)) van hanh vi cua tre*.