Adding posts into product pages

Hello! I encounter a struggle with adding a simple block or widget with relevant posts into single products’ pages. I know how to do it vice versa – adding blocks of products into various posts, but not how to add posts into products. I tried various things but nothing seems to work as if the Woocommerce didn’t allow for such action. Is there anything that I’m missing or is really impossible? I would greatly appreciate any guidance on it.

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