Google never picks up the snippets describing a post, as I have written them in my Metadescription (using Yoast SEO plugin).

eg: My Metadescription for the ‘Loving Vincent’ review is as follows:
Visually, Loving Vincent is unmissable – a unique hand-painted animated work in Van Gogh’s style. Dramatically, it’s ho-hum.

The snippet Google picks up changes each time I search for “Loving Vincent movie review” and browse through the pages until I find my post listed. The most recent entry has: “It’s not as if a film like this is likely to have mass appeal in the Anglo marketplace. In summary, Loving Vincent is unmissable for its visuals, …

If anyone could advise how I can ensure that Google shows the Metadescription as I have written it, would be most appreciative.