Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
vu hanh » vu khanh, vu thanh, du hanh
hanh ky » hanh kem
cac xuc » cam xuc, cac nuoc, chat xuc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, 5 hoi

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: vu hanh ky nang ((x hoi) OR (x ho)). hieu vien cac xuc ((va hanh) OR (gia thanh)) vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu hanh ky nang ((x hoi) OR (x ho)). hieu vien cac xuc ((va hanh) or (gia thanh)) vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: vu hanh ky nang ((x hoi) OR (x ho)). hieu vien cac xuc ((va hanh) or (gia thanh)) vi cua tre*.