I optimized a site with 20 keywords. I was checking the ranking of the keywords but none of the 20 keywords are within top 100 of any search engines. Wht could be the problem?
It takes a while for the search engines to update. Also do you have many inbound links with the keywords as the anchor text? SEO isn't all onsite, you need to work on building link bait, otherwise you'll never rank for competitive terms.
Yes, seems you're targeting highly competitive keywords, check did you placed keywords in your title tag, anchor text, site content?
You should get to gather quality back links and with certain keywords as your anchor text. How many months have you been working on that? If it really has a big keyword competition, it will be really tough to rank on the SE's...
Search engine optimization involves many things: linking, copy writing, navigation, designs, menus, content, etc… and lot more. The question is, did you do those things for you site? It is not the job of Search Engine Optimization to make a pig fly. It is the job of the SEO to genetically re-engineer the web site so that it becomes an eagle.
It may also depend upon the keywords density on your site content if you optimize that site with main keywords density increases a limit then google consider it as a spam.
It is hard to optimise a page for 20 keywords.... too much dilution in content. Maybe you did not do proper optimisation