It seems that when we use the search box on our website (https://onetreeplanted.org), only blog posts and product pages display a featured image/thumbnail.
However, none of our “regular” pages display an image.
See the example below, when we search for “climate change”, only blog posts display an image, but the actual “climate change” page does not have an image:
By default a page has no placeholder for any image. What you can do is implement a generic image that will display for all pages. I believe you’re using the Theme search correct?