Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
hanh dai » hanh tai, hanh dao, vanh dai
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
cam duc » cam xuc, cao duc, pham duc
duc ban » duc tan, duc van, dua ban
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su xac
su cac » tu cac, su cao, su can

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sac) or (su cac)) ky nang xa hoi. ((hieu ve) or (hieu van)) cam duc ban hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sac) OR (su cac)) ky nang xa hoi. ((hieu ve) OR (hieu van)) cam duc ban hanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sac) or (su cac)) ky nang xa hoi. ((hieu ve) or (hieu van)) cam duc ban hanh dai cua tre*.