[Plugin: Google XML Sitemaps] Google XML Sitemap not notifies all major search engines every time

Google XML Sitemap not notifies all major search engines every time i create a post about the new content, every time i need to resubmit the sitemap on the webmaster, please help.
I am using Google XML Sitemap Version 3.2.6, can any one help me on this.

http://wordpress.org/extend/plugins/google-sitemap-generator/