Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
hieu viec » nhieu viec, sieu viet, hieu hien
dung doi » huong doi, dung tai, dung co
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
doi cua » dai cua, hoi cua
va dung » van dung, va duong, vat dung
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang xa) OR (nang x)) hoi. ((hieu viec) or (hieu ve)) sach nuoc va dung doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (nang x)) hoi. ((hieu viec) OR (hieu ve)) sach nuoc va dung doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang xa) OR (nang x)) hoi. ((hieu viec) or (hieu ve)) sach nuoc va dung doi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) OR (nang x)) hoi. ((hieu viec) or (hieu ve)) sach nuoc va dung doi cua tre*.