use strict;
use warnings;

use Win32::OLE             qw( );
use Win32::OLE::Variant; # qw( Variant VT_* );

my $IE = Win32::OLE->new("InternetExplorer.Application")
   or die("Could not start Internet Explorer.Application\n");
 
$IE->{visible} = 1;

my $url       = "http://amos.shop.com/amos/cc/main/ccn_search/ccsyn/150/stid/6150608";
my $post_data = "search_form=&st=socks&sy=products&search_button.x=39&search_button.y=12";

$IE->Navigate(
   $url,
   undef,
   undef,
   Variant(VT_UI1, $post_data),
   "Content-Type: application/x-www-form-urlencoded\r\n",
);

# Alternative Syntax
# ==================
#
# $IE->Navigate($url, {
#    PostData => Variant(VT_UI1, $post_data),
#    Headers  => "Content-Type: application/x-www-form-urlencoded\r\n",
# });

##</code><code>##

REQUEST_METHOD=POST
CONTENT_LENGTH=71
CONTENT_TYPE=application/x-www-form-urlencoded

Content length: 71
Content (hex):  7365617263685f666f726d3d2673743d736f636b732673793d70726f6475637473267365617263685f627574746f6e2e783d3339267365617263685f627574746f6e2e793d3132
Content:        search_form=&st=socks&sy=products&search_button.x=39&search_button.y=12