Not Ranking

According to webmaster tools my site is ranking and the avg position is 4.7? But when i search on google, its not in the top 100. it seems like the site is getting impressions and hits but it doesnt seem to be ranking for my main keyword when i search however webmaster tools suggests it does. strange. can anyone explain ?

ps sorry for the small image, still new to forum. if you click it expands

Webmasters tools is so bad, use something else. It is never accurate.

The ranking reports generated by Google Webmaster Tools display the average of your site's ranking positions for each keyword over a certain period of time. To get accurate and real ranking reports, use a rank tracker like serpfox.