Perhaps you should try some spelling variations:
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
van hanh » van thanh, ban hanh, van ban
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
van anh » van thanh, tuan anh, van minh
lam cua » nam cua, lam chat
cua tre » cua te, cuu tre, cua triet

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 ((nang xa) OR (nang x)) hoi. hieu va cac nuoc ((van hanh) OR (van anh)) lam cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang xa) or (nang x)) hoi. hieu va cac nuoc ((van hanh) OR (van anh)) lam cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) or (nang x)) hoi. hieu va cac nuoc ((van hanh) OR (van anh)) lam cua tre*.