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

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) nang ma hoi. hieu ((ve cam) OR (ve cac)) duc ban thanh tai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) or (sach y)) nang ma hoi. hieu ((ve cam) OR (ve cac)) duc ban thanh tai cua tre~".
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) or (sach y)) nang ma hoi. hieu ((ve cam) OR (ve cac)) duc ban thanh tai cua tre*.