Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach ky » sac ky, sach y, sach ty
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
cau tuc » cau truc, cau tu, cau luc
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
tuc va » thuc va, truc va, tuc xa
di cua » dai cua, doi cua, de cua
o hai » co hai, so hai, o lai
x hoi » xa hoi, o hoi, x ho

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 nang ((x hoi) OR (o hai)). ((hieu ve) OR (hieu va)) cau tuc va hanh di cua tre~.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((x hoi) or (o hai)). ((hieu ve) or (hieu va)) cau tuc va hanh di cua tre*.