Perhaps you should try some spelling variations:
ban hanh » ban hang
tru nang » tra nang, tri nang, truc nano
tu cach » tu cac
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
su sach » so sach, vu sach
va nam » van nam, ha nam
va nay » va ngay, va cay
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

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