Disable Certain Sidebox on Home Page

[CoolCarPartsOnline]

I am trying to display certain sideboxes on home page only. I will disabling the right column on the home page, I want to display the Search sidebox in the left column so I cloned the search sidebox and renamed it to search_left_home_page.php.
I edited the code based on other threads I read in the forum about disabling single sidebox on the home page. But now the code I added hides the sidebox on home page and display it on other pages. Here is the link to the site www.ohiospeedshop.com and the code I am using is:

<?php
/**
 * search sidebox - displays keyword-search field for customer to initiate a search
 *
 * @package templateSystem
 * @copyright Copyright 2003-2005 Zen Cart Development Team
 * @copyright Portions Copyright 2003 osCommerce
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 * @version $Id: search.php 2834 2006-01-11 22:16:37Z birdbrain $
 */
 //display on home page only
  if ($this_is_home_page) {
    $show_search_left_home_page = false;
  } else {
    $show_search_left_home_page = true;
  
  require($template->get_template_dir('tpl_search_left_home_page.php',DIR_WS_TEMPLATE, $current_page_base,'sideboxes'). '/tpl_search_left_home_page.php');

  $title = '<label>' . BOX_HEADING_SEARCH . '</label>';
  $title_link = false;
  require($template->get_template_dir($column_box_default, DIR_WS_TEMPLATE, $current_page_base,'common') . '/' . $column_box_default);

}
?>