When I search Google with site:catalogue.cappiello.fr "Leonetto Cappiello affiches", it shows only one image as a preview. However, a specific page on the same site, like https://catalogue.cappiello.fr/creation-dune-affiche/, shows three preview images for the same query. Why does this happen?
I have more than 3000 products / pics on my site, and all products have been imported with the same method. So, for all pics, pic name has been generated to include keywords, I have set alt text, title, caption, and description. I also can see all images are indexed on Google images, so this seems not to be a indexation issue.
Why is the result aleatory ? What should I do to fix it ?