How should I set up the thumbnails that appear in the rich results on the Google search screen?

Please tell me about Rich Results on the Google search results screen.
The thumbnail displayed as Rich Results is not the thumbnail I want.
Currently, the images on the site are displayed as the thumbnails.

The following countermeasures have been implemented so far.

1.Structured data settings
2.OGP settings
3.Settings in the sitemap (sitemap.xml)
4. settings

If these measures do not solve the problem, what other solutions are possible?