Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
chua tre » chua tri, chua trieu, cho tre
tu sach » thu sach, te sach, tu cach
giao va » gia va, giai va, gian va
da giao » dan giao, dai giao, dao giao
vien da » vien dai, hien dai
nang xa » nang x, lang xa, nang ma
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
va dau » va dao
dau va » dau ve, lau va

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

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