dem_queries.php

$taxonomies = Fusion()->get_content_taxonomies();

foreach ( $taxonomies as $taxonomy ) {
	$tax_query['tax_query'][] = array(
		'field' => 'term_id',
		'terms' => $tags,
		'taxonomy' => $taxonomy,
	);
}

$tax_query['tax_query']['relation'] = 'OR';
$tax_query['posts_per_page'] = $requested_posts;
$tax_query['post_type'] = Fusion()->get_content_post_types();

$related_content = new WP_Query( $tax_query );