If metabox has content display content.

I know how to display field content if the field has content.

$monday = get_post_meta($post->ID, '_cmb_open_monday', true);
if ( ! empty ( $monday ) ) {
echo 'content';
}

How do I display the content if one of the fields from the metabox “store_openingtimes” has content? Maby this explains better what i want to do:

$storeopen = Get all meta from metabox id "store_openingtimes"
if ( ! empty ( $storeopen ) ) {
echo 'content';
}