How to get multiple page templates

Hi, i have some code which successfully creates the variable based on the page template.

$courses = get_pages_by_template('page-template-1', $post->ID);

But I need this to get 2 templates at once, the below doesn’t work any suggestions?

$courses = get_pages_by_template('page-template-1'&&'page-template-2', $post->ID);