Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
hieu viec » nhieu viec, sieu viet, hieu hien
danh dai » danh dau, danh di, danh sai
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, va hanh
cua tre » cua te, cuu tre, cua triet

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

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