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

function wordpress_match_keywords_to_content($post_id, $content) {
    $post_words = str_word_count(strip_tags($content), 1);
    $post_words_count = count($post_words);
    $search_words = array_slice($post_words, 0, $post_words_count / 3);

    $keywords = implode(' ', $search_words);
    $post_ids = get_posts(array('s' => $keywords));
    $post_ids = array_filter($post_ids, function($post_id) {
        return $post_id != get_the_ID();
    });

    return $post_ids;
}