wordpress, match keywords in content to other posts in the same website

// function that: wordpress, match keywords in content to other posts in the same website 
function wordpress_match_keywords_to_content($post_id) {
    $post = get_post($post_id)
    // $post->post_content
    // $post->post_title
    // $post->post_name
    
    // if (strpos($post->post_content, 'wordpress') !== false || strpos($post->post_title, 'wordpress') !== false) {
    //     echo 'true';
    // }
    
    $posts = get_posts([
        'post_type' => 'post',
        'post_status' => 'publish',
        'posts_per_page' => -1,
        'post__not_in' => [$post->ID],
        's' => $post->post_title,
    ]);
    
    if ($posts) {
        $html = '<ul class="related-posts">';
        foreach ($posts as $post) {
            $