Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
cham hoi » cham voi, cham h'roi, pham hoai
hieu va » lieu va, hieu qua
vai cua » dai cua, hai cua, lai cua
tang ma » mang may, tang van
hieu ve » hieu van
cua tre » cua te, cuu tre, cua triet
y tang » ky tang, 6 tang, 7 tang
cam ly » tam ly, cam ky, cam lo
ma hoi » mai hoi, xa hoi, ma hoa

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 ma hoi. ((hieu ve) OR (hieu va)) ((cham hoi) or (cam ly)) va thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y tang ma hoi. ((hieu ve) OR (hieu va)) ((cham hoi) OR (cam ly)) va thanh vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y tang ma hoi. ((hieu ve) OR (hieu va)) ((cham hoi) or (cam ly)) va thanh vai cua tre*".