Show only certain post IDs

Hello and good day.
On one page I want to show 6 testimonials but I want to show certain 6. How do I do that?

This is what I have now:
<?php do_action( ‘woothemes_testimonials’, array( ‘limit’ => 6 ) ); ?>

When I try to add the ID to the Array it only show me one. So how do I show more than one certain ID in part of this certain group? Thank you 🙂

https://ww.wp.xz.cn/plugins/testimonials-by-woothemes/