Perhaps you should try some spelling variations:
ban hanh » ban hang
tu sach » thu sach, su sach, tu cach
te sach » toc sach
hieu ve » hieu va, hieu van
cao duc » dao duc, cao suc, giao duc
duc ban » duc tan, duc van, dua ban
cua tre » cua te, cuu tre, cua triet
ve cao » va cao, ve bao, ve cac
vi cua » vai cua, di cua
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (te sach)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao duc ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao duc ban hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao duc ban hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao duc ban hanh vi cua tre*.