I suggest reading some of the documentation, more specifically this section.
To answer your question...
I assume your Help model has a unique key controller+action.
In your controller's method you will need:
$help = $this->Help->findByControllerAndAction($controller ,$action);
if ($help) {
$this->set('help', $help);
}
In your view:
echo $help['Help']['controller'];
will show the content of the Help.controller field.
Use:
debug($help);
If $help is not defined in your view, chances are your find is not returning the results you expect.