Try this..
$terms = get_the_terms( $post->ID, 'tag_blogcom' );
foreach ($terms as $term) {
$slugs[] = $term->slug;
}
$query = new WP_Query( array(
'post_type' => 'blogcom',
'tax_query' => array(
array(
'taxonomy' => 'tag_blogcom',
'field' => 'slug',
'terms' => $slugs,
),
),
'posts_per_page' => 10
)
);
Check the Taxonomy Parameters at WordPress Codex.