Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
thanh dai » thanh tai, thanh dat, thanh oai
cam duc » cam xuc, cao duc, pham duc
duc ban » duc tan, duc van, dua ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach kem
hieu va » lieu va, hieu qua
may hoi » may thoi, tay hoi, mai hoi
sach ty » sach y, sach tu, sach thu
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ky) OR (sach ty)) mang may hoi. hieu va cam duc ban ((thanh dai) or (thanh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach ty)) mang may hoi. hieu va cam duc ban ((thanh dai) OR (thanh hai)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach ty)) mang may hoi. hieu va cam duc ban ((thanh dai) or (thanh hai)) cua tre*".