macmanx on "Ayuda con los botones de la página"

You can't add Share This, but we do have our own sharing buttons available via Settings -> Sharing in your blog's Dashboard.

http://en.support.wordpress.com/sharing/

I'm not sure what you mean by the first request. Do you want to add a search ability to each page? If so, you can add a Search widget from Appearance -> Widgets in your blog's Dashboard.