My new site link was captured by google. but i m using high density keyword still my link displayed very far on google search. Can i change my keyword and site title again? does it affect my site? it is starting stage for my site.
Yes You can change it. you can change your keywords, title, description but do according to webmaster guidelines.
you said your site link is new so no problem in doing experiments with it. you can very well do modifications in title and keywords. but first do keyword research and then apply appropriate keywords at appropriate places.
yes, change it and be patient with google, Those things can take time. Make sure to update your site regularly, so the google boat spider, will come to visit you often.
you can change the leywords of the site any time, But you should have some good backlink for the same keyword.
you can change it and wait for google to crawl again your site and you'll now see the changes on your titles, keywords and description
Probably you're targeting highly competitive keywords, IMO instead of changing the title tags you should add few potential keyword phrases in your text/anchor text, hope this could help you to rank better for some potential keyword phrases.