Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh han » hanh nhan, hanh phan, hanh san
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
cam duc » cam xuc, pham duc, nam duoc
cao duc » dao duc, cao suc, giao duc
han cua » hang cua, nhan cua, than cua
cua tre » cua te, cuu tre, cua triet
su dan » su dang, cu dan, so dan
dan ky » van ky

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

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