Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
qua cac » cua cac
cac duc » cac du, cao duc, cac dac
duc van » duc va, duc tan, duc manh
vai cua » dai cua, hai cua, lai cua
cua chu » sua chua
o hoi » co hoi, o hoc, o hai

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

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