Perhaps you should try some spelling variations:
nhieu vien » nhieu viec, nhiet dien, thieu nien
vien cac » vien bach, vien dai, vien da
trinh vi » trinh va, trinh viet, trinh van
trinh ve » trinh he, trinh va, trinh viet
cac duc » cac du, cao duc, cac dac
te sach » toc sach
nang xa » nang x, lang xa, nang ma
su sach » so sach, vu sach
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: ((te sach) or (su sach)) ky nang xa hoi. nhieu vien cac duc va ((trinh ve) OR (trinh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (su sach)) ky nang xa hoi. nhieu vien cac duc va ((trinh ve) OR (trinh vi)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (su sach)) ky nang xa hoi. nhieu vien cac duc va ((trinh ve) OR (trinh vi)) cua tre*".