Search in Custom Post Types

functions.php

https://developer.wordpress.org/themes/template-files-section/custom-post-type-template-files/
By default search results do not include custom post type content into the search results. The code can be appended to functions.php to include CPT in search results :

// Show posts of 'post', 'page', 'acme_product' and 'movie' post types on home page
function search_filter( $query ) {
  if ( !is_admin() && $query->is_main_query() ) {
    if ( $query->is_search ) {
      $query->set( 'post_type', array( 'post', 'page', 'acme_product', 'movie' ) );
    }
  }
}
 
add_action( 'pre_get_posts','search_filter' );