Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
sach ky » sach y, sach ty, sach kem
tai cua » thai cua, tai cuc, tri cua
cuu ban » cuu van, cua ban, cuu san
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky
ve cac » vien cac

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