Hi i have a site that is ranked well for a keywords. but now i am getting greedy and i want to get some more traffic from other keywords also. so can i buy new domain names and put this existing sites on it and then change the keywords of this site? or would it be penalized by search engines for duplicate content. please help me.

It will definately be a copy content issue.

To target other keywords you don't need another domain name you can optimize your existing site to target multiple keywords with a single site.

And if still you want to go with different sites then they should have unique content in my opinion.

Ok understand thank you for the reply.