Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
hieu viec » nhieu viec, hieu ve, sieu viet
danh doi » danh di, thanh doi, dung doi
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cua triet, dua tren
va danh » va dinh, va dan, va hanh
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cuu tre » cau tren, cau treo

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