In the post Google Penguin 2.0 era it is critical that your website is properly optimised for the search engines and free from technical errors.
Each page requires a unique page title and meta description tag of the appropriate length. Your main keywords should be included in both of those fields as well as being featured as header text and body text on the page. It is important to have a sufficient quantity of words on the page and avoid keyword stuffing. All images should be labelled and you should avoid excessive internal and external links.
Web Predators can provide a detailed analysis of your site's optimisation level and advise about any changes that may be required in order to resolve any technical errors or warnings.