Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
cham giua » tham gia, nhat giua, cam gia
thanh hoi » thanh hoai, thanh hoa, thanh hai
giua ban » giup ban, dia ban, cua ban
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, lai hoi, mai doi
dai hoi » dai hoc, dai hai, dai moi
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
hoi cuu » hoi chu, hoi cua, ho cuu
cuu tre » cua tre, cau tren, cau treo

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 nang ((mai hoi) or (dai hoi)). hieu ve cham giua ban thanh hoi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((mai hoi) OR (dai hoi)). hieu ve cham giua ban thanh hoi cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((mai hoi) or (dai hoi)). hieu ve cham giua ban thanh hoi cuu tre*.