Associate assets to webpage domain

So, when I upload assets (images, PDFs, etc) to Contentful, I can access them via and respectively. These assets are supposed to be used on a website and theoretically should associate with the domain of that website.

Yet, because technically assets are not using the same domain as that of the website, search engines will not associate the assets to the website’s domain.

Are there any ways, both on the Contentful side and on my code, what I can do to “hint” the search engines such that it will associate the assets to my domain instead?