Calling views fast search from php

Looking for a little guidance on how I can call the search from a PHP file. (I want to be able to use a value from a story node as the search word).

I assume it would be something like this, but I couldn't find any documentation on what I should pass to the search function.

$view = views_get_view('related_content');
print views_build_view('embed', $view, array($title), false, 8);