Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
hieu viec » nhieu viec, sieu viet, hieu hien
vu khach » vu khanh, vu khac, vay khach
danh doi » danh di, thanh doi, dung doi
cua tre » cua te, cua triet, dua tren
va danh » va dinh, va dan, va hanh
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
cuu tre » cau tren, cau treo
y nang » ky nang, ly nang, v nang

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

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