Custom post type search only title WP_query and title capital and small latter issue

Post title: "Test"

when i am searching "test" then autosuggestion not showing result but when search First word Capital "Test" then autosuggestion showing.

How to solve it?

Please response Thank You

$results = new WP_Query( array(
                'post_type'     => array( 'dream'),
                'post_status'   => 'publish',
                'posts_per_page'=> 221,
                's' => stripslashes($_POST['search'])
                //'s' => $search_key,
                //'title'     => 'true',
            ));
            $items = array();
            if ($results->have_posts()) {
                while ( $results->have_posts() ) : $results->the_post();                
                    $items[] = get_the_title();  
               endwhile;
            }

source https://stackoverflow.com/questions/76789797/custom-post-type-search-only-title-wp-query-and-title-capital-and-small-latter-i