Perhaps you should try some spelling variations:
thien van » thi van
thu sach » tu sach, thuat sach, thuoc sach
cau thuc » cau truc, cuu thuc, can thuc
cua tre » cua te, cua triet, dua tren
hanh de » hanh ve, hanh kem
hanh di » hanh vi, hang di, danh di
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
van cau » van dau, van hau, van chat
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
cuu tre » cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa

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: thu sach ky tang ma hoi. thien van cau thuc va ((hanh di) OR (hanh de)) ((cua tre) OR (cuu tre))~.
• Adding a wildcard symbol may retrieve word variants: thu sach ky tang ma hoi. thien van cau thuc va ((hanh di) or (hanh de)) ((cua tre) or (cuu tre))*.