We have renamed the archive-product.php because it does not include any custom code but our code added in the last update was missing. So, search by products and posts/pages works. We found that if this option of the third-party plugin is enabled ttp://prntscr.com/pjze9h
then search results are duplicated http://prntscr.com/pjzgc4 We are not sure why this plugin affects the search results but keep that option disable to avoid that issue.
