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 mo
su sach » so sach, vu sach
dung co » dung cho, dung cong, dung cua
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
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: su sach y nang xa hoi. ((hieu viec) or (hieu ve)) sach nuoc va ((dung doi) OR (dung co)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang xa hoi. ((hieu viec) OR (hieu ve)) sach nuoc va ((dung doi) OR (dung co)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang xa hoi. ((hieu viec) or (hieu ve)) sach nuoc va ((dung doi) OR (dung co)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach y nang xa hoi. ((hieu viec) or (hieu ve)) sach nuoc va ((dung doi) OR (dung co)) cua tre*.