SELECT DISTINCT wp_posts.post_title
                                            FROM        wp_posts                       
                                            WHERE       wp_posts.post_type = 'palabra'
                                            AND         wp_posts.post_status = 'publish'
                                            AND         wp_posts.post_title BETWEEN 'Chile prieto' AND 'zzz'
                                            ORDER BY    wp_posts.post_title ASC
                                            LIMIT       6