Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
thu sach » tu sach, thuat sach, thuoc sach
cham hoi » cham voi, cham h'roi, pham hoai
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
y tang » ky tang, 6 tang, 7 tang
cam ly » tam ly, cam ky, cam lo

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((y tang) or (ky dang)) mai hoi. hieu ve ((cham hoi) or (cam ly)) ban thanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y tang) OR (ky dang)) mai hoi. hieu ve ((cham hoi) OR (cam ly)) ban thanh vai cuu tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ((y tang) or (ky dang)) mai hoi. hieu ve ((cham hoi) or (cam ly)) ban thanh vai cuu tre*.