Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, anh thai
hanh tai » thanh tai, hang tai, han tai
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
cac dac » cac dan, cac dai, cac bac
cao duc » dao duc, cao suc, giao duc
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
nang o » nang co, nang ho, nang ro
o lai » o lao

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 sac ky nang o lai. hieu ve ((cac dac) OR (cao duc)) van ((hanh thai) OR (hanh tai)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang o lai. hieu ve ((cac dac) or (cao duc)) van ((hanh thai) OR (hanh tai)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang o lai. hieu ve ((cac dac) or (cao duc)) van ((hanh thai) OR (hanh tai)) cua tre*.