Perhaps you should try some spelling variations:
hieu vien » hieu hien, thieu nien, hieu tieng
hieu viec » nhieu viec, hieu ve, sieu viet
sach nuoc » sach duoc, cac nuoc, bach tuoc
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cuu tre » cua tre, cau tren, cau treo
di cuu » di cau, di cua, dinh cuu

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 vien) or (hieu viec)) sach nuoc va hanh di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. ((hieu vien) OR (hieu viec)) sach nuoc va hanh di cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. ((hieu vien) or (hieu viec)) sach nuoc va hanh di cuu tre*.