Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh lai » thanh hai, thanh lap, thanh loi
duoc ban » duc ban, quoc ban, buoc ban
sach ky » sach y, sach ty, sach kem
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
va nam » van nam, ha nam
va nay » va ngay, va cay
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 ((sach ky) or (sac ky)) nang x hoi. lieu ((va nam) OR (va nay)) duoc ban thanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. lieu ((va nam) OR (va nay)) duoc ban thanh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang x hoi. lieu ((va nam) OR (va nay)) duoc ban thanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang x hoi. lieu ((va nam) OR (va nay)) duoc ban thanh lai cua tre*.