Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh ha » thanh hoa, thanh hai, nhanh ha
cham duc » pham duc, cham soc, pham duy
hieu ve » hieu va, hieu van
duc ban » duc tan, duc van, dua ban
ve cham » va cham, ve chat, vu cham
tu sach » thu sach, su sach, te sach
hoa hoi » khoa hoi, hoa hoc, hoa doi
cua tre » cua te, cuu tre, cua triet
sach 7 » sach y, sach 2
ha hoi » ha noi, xa hoi, va hoi
7 tang » 6 tang
ha cua » hoa cua, hai cua, nha cua

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 7 tang ((ha hoi) or (hoa hoi)). hieu ve cham duc ban thanh ha cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach 7 tang ((ha hoi) OR (hoa hoi)). hieu ve cham duc ban thanh ha cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach 7 tang ((ha hoi) or (hoa hoi)). hieu ve cham duc ban thanh ha cua tre*.