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Whenever $results_desc->feed_product_desc is empty, the post content is used. Otherwise the content is never used.

if (!empty($results_desc->feed_product_desc)){
    $content = $results_desc->feed_product_desc;
} else {
    $content = get_the_content();
    $content = strip_tags($content);
}

Whenever the post content is used, all HTML tags are stripped.

$content = get_the_content();
$content = strip_tags($content);

To get the full content with all the tags, use just the first line:

$content = get_the_content();