Perhaps you should try some spelling variations:
tu cach » tu cac
tay hoi » tay ho, tao hoi, tay thai
va hanh » van hanh, va thanh, va danh
cac xuc » cam xuc, cac nuoc, chat xuc
qua cac » cua cac
cua tre » cua te, cuu tre, cua triet
xay hoi » xa hoi, cay phoi, gay thoi
ky dang » ky nang, ky danh
su sach » so sach, vu sach
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: ((tu cach) or (su sach)) ky dang ((xay hoi) OR (tay hoi)). hieu qua cac xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (su sach)) ky dang ((xay hoi) OR (tay hoi)). hieu qua cac xuc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (su sach)) ky dang ((xay hoi) OR (tay hoi)). hieu qua cac xuc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (su sach)) ky dang ((xay hoi) OR (tay hoi)). hieu qua cac xuc va hanh vi cua tre*.