node theming and search result theming

Hi, I am using the theme zero point and i am very happy with it. I want to theme one of my node advertisement, I copy the node.tpl.php and the copy file i renamed it with node-advertisement.tpl.php and it didn't work, may there is a naming convention that must be used aside from the normal drupal way, and also I want to theme the search result page also to include pictures please show me how. Thanks a lot it would be a great help.

Thanks