related_newsletter_articles

$tax_query = array(
	'relation' => 'AND',
	array(
		'taxonomy'         => 'related_newsletter',
		'terms'            => '2019',
		'field'            => 'name',
		'operator'         => 'AND',
	),
	array(
		'taxonomy'         => 'related_newsletter',
		'terms'            => 'December',
		'field'            => 'name',
	),
);