Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
hieu viec » nhieu viec, hieu ve, sieu viet
hieu van » hieu va, thien van, lieu va
danh dai » danh dau, danh di, danh sai
su sach » vu sach
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
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: ((su sach) or (so sach)) ky nang xa hoi. ((hieu viec) or (hieu van)) sach nuoc va danh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky nang xa hoi. ((hieu viec) OR (hieu van)) sach nuoc va danh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky nang xa hoi. ((hieu viec) or (hieu van)) sach nuoc va danh dai cua tre*.