Include tags in my search

I have a search function on my WordPress site, and I’ve only just noticed that it doesn’t seem to include my custom post-type’s tags in the search. It is absolutely essential that my search includes tags when searching, so I wondered whether there is a simple solution here? I have looked on the net but can’t seem to find a solution anywhere!

Here’s my html:

<ul>
    <?php if ( have_posts() ) : ?>
    <?php while ( have_posts() ) : the_post(); ?>
    <li class="resultItem">
        <?php if (has_post_thumbnail( $post->ID )): ?>
            <?php $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'full' ); ?>
            <a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title(); ?>"><img src="<?php bloginfo('template_directory'); ?>/thumbs.php?src=<?php echo $image[0]; ?>&w=120&h=120&zc=1" alt="<?php the_title(); ?>" /></a>
        <?php endif; ?>
        <div id="resultText">
            <h2 class="redSubHeader"><a href="<?php the_permalink() ?>" title="<?php the_title(); ?>"><?php the_title(); ?></a></h2>
            <?php the_excerpt(); ?>
        </div>
    </li>
    <?php endwhile;?>
</ul>

And here’s the php which makes my search only search within the ‘event’ custom post-type:

// Only search for Events post-type in keyword search

function SearchFilter($query) {
if ($query->is_search) {
$query->set('post_type', 'events');
}
return $query;
}

add_filter('pre_get_posts','SearchFilter');

Thanks guys ??