wp_remote_get- download with arguments

I need to download page from wp/admin. I use function wp remote get, which allows get a remote URL with special arguments. My code is:

$args = array( 'cookies' => $cookies,'httpversion' => '1.1','timeout' => 120);
$page=wp_remote_get("http://saluta.cz/villarichter/wp-admin/post.php?post=52", $args);

But this just download list of post (post.php without arguments), not requested edit page. I am sure that post 52 is exists.
PS.: I need download that page to get some nonces, so if you know another way to get it, I would be delighted.