Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
sach ky » sac ky, sach y, sach ty
van cac » van cau, van bac, dan cac
van hac » van hoc, van ha, van hai
cua tre » cua te, cuu tre, cua triet
so hai » son hai, su hai, so ha
co hoi » co hoc, co loi
bo van » vo van, so van, do van
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang ((so hai) or (co hoi)). hieu ((van cac) or (van hac)) bo van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((so hai) OR (co hoi)). hieu ((van cac) OR (van hac)) bo van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((so hai) or (co hoi)). hieu ((van cac) or (van hac)) bo van hanh vi cua tre*.