Perhaps you should try some spelling variations:
ninh viet » sinh vien, anh viet
viet cua » viec cua, viet ca, viet qua
khien tu » dien tu
tu cach » tu cac
vuc van » duc van, luc van, thuc van
xuc van » duc van, luc van, xuc ban
tu chat » tu phat, tu cham, du chat
so sanh » do sanh
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (so sanh)) ky nang x hoi. khien tu chat ((xuc van) OR (vuc van)) ninh viet cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (so sanh)) ky nang x hoi. khien tu chat ((xuc van) OR (vuc van)) ninh viet cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (so sanh)) ky nang x hoi. khien tu chat ((xuc van) OR (vuc van)) ninh viet cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (so sanh)) ky nang x hoi. khien tu chat ((xuc van) OR (vuc van)) ninh viet cua tre*.