Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ky dang » ky nang, ky danh
xay hoi » tay hoi, cay phoi, gay thoi
hieu ve » hieu va
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
tai ky » thai ky, trai ky, sai ky
xuc va » duc va, tuc va, luc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te tai ky dang ((xay hoi) or (xa hoi)). ((hieu ve) OR (hieu van)) cam xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te tai ky dang ((xay hoi) OR (xa hoi)). ((hieu ve) OR (hieu van)) cam xuc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te tai ky dang ((xay hoi) or (xa hoi)). ((hieu ve) OR (hieu van)) cam xuc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te tai ky dang ((xay hoi) or (xa hoi)). ((hieu ve) OR (hieu van)) cam xuc va hanh vi cua tre*.