How to get articles from a custom field to display to a specific post

Hy im building a cinema site..

http://cinema.trancelevel.com/amazing-spider-man-2012/

How can i get the news that contain the movie title…

For example i have this :

<?php
$recentPosts = new WP_Query();
$recentPosts->query(array('showposts' => 1, 'post_type' =>array('stiri')));
?>
<?php while ($recentPosts->have_posts()) : $recentPosts->the_post(); ?>
<div class="sidebar-titlu"><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></div>
<div class="sidebar-stiri">
<img src="/scripts/timthumb.php?src=<?php the_field('imagine_stire'); ?>&h=60&w=90&zc=1" alt="" title="<?php the_title(); ?>" />
<?php $excerpt = get_the_excerpt();echo string_limit_words($excerpt,30);?><a class="detalii" href="<?php the_permalink() ?>" rel="bookmark" title="<?php printf(__('%s'), the_title_attribute('echo=0')); ?>">...detalii</a>
</div>
</div>
<?php endwhile; ?>
<ul>
<?php
$recentPosts = new WP_Query();
$recentPosts->query(array('showposts' => 5, 'post_type' =>array('stiri')));
?>
<?php while ($recentPosts->have_posts()) : $recentPosts->the_post(); ?>
<li><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></li>
<?php endwhile; ?>
</ul>

How can i get the news by tag.

For example: if i have a news and have tag the Amaizing Spiderman….i want to apear in the right in sidebar.

For Movies – i use POST
For Stiri – i use post_type

If ennybody knows please post… or how can i get the news other way… custom field… etc…

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