Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
van dinh » van minh, van dich, va dinh
dinh vai » dinh van, dinh vi, dinh va
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
cac bo » bac bo, cac co
bo van » vo van, so van, do van

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (su sach)) ky nang xa hoi. hieu vien cac bo van dinh vai 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 cac bo van dinh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) ky nang xa hoi. hieu vien cac bo van dinh vai cua tre*.