According to the 4th Wave Observatory of Social Networks of BBVA, the existence of Facebook stores are mostly unknown in the middle of 2012.
The solution is very easy, using a specific tag such as
Additionally, there are more tags to be used in Facebook, we can detail other parameters when we share a link such as the image that appears with the link, title, etc.
A common problem is that despite these metatags have been incorporated into your website, you can continue seeing the ancient description. That means that your page is in the cache of facebook and you have to delete it. Simply go to Facebook debugger and introduce your website, it will remove the cache of Facebook and publish information containing your metatags.