Search.php ile, istedğim Kategorilerde Arama Yaptırma?!

<?php get_header(); ?>

<div id="pagewrap">
<div id="content">
<div id="contentleft">
<div id="menubar">
<div id="catlist">
<ul class="menu">
<li><a href="#menu" onclick="javascript:showlayer('sm_1')">Select a Category</a></li>
<ul class="submenu" id="sm_1">
<?php wp_list_categories('&title_li='); ?>
</ul>
</ul>
</div>

<a title="Subscribe to Content via RSS" href="<?php bloginfo('rss2_url'); ?>"><div id="subscribe"></div></a>
</div>

<div id="videogallery">
<?php if (have_posts()) : while (have_posts()) : the_post(); ?>
<div class="videoitem">
<div class="ratings">
<?php if(function_exists('the_ratings')) { the_ratings(); } ?>
</div>

<div class="comments">
<?php comments_number('0', '1', '%'); ?>
</div>

<div class="thumbnail">
<a href="<?php the_permalink() ?>" title="<?php the_title() ?>"><img style="background: url(<?php $key="thumbnail"; echo get_post_meta($post->ID, $key, true); ?>)" class="thumb" src="<?php bloginfo('template_url'); ?>/images/zoom.png" alt="<?php the_title() ?>" /></a>
</div>

<h2 class="itemtitle"><a href="<?php the_permalink() ?>" title="<?php the_title() ?>"><?php the_title() ?></a></h2>
<p class="itemdesc"><?php the_content_rss('', TRUE, '', 8); ?></p>
<small class="gallerydate"><?php the_time('F j, Y'); ?></small>
</div>
<?php endwhile; else: ?>

<div class="pageitem">
<h2>Sorry... But What You Are Looking For Isn't Here!</h2>
<div class="blogcontent">
Try Searching for something else or click the logo to go to the home page.
</div>
</div>

<?php endif; ?>

<div id="pagenav">
<?php if(function_exists('wp_pagenavi')) { wp_pagenavi(); } ?>
</div>
</div>
</div>

<div id="contentright">
<?php get_sidebar(); ?>
</div>
</div>
</div>

<?php get_footer(); ?>