How to Include Specific Custom Post Types in WordPress Search Results

Custom post types are not included in the WordPress search results by default – adding this snippet to your functions.php creates a function that allows specific custom post types to be queried and searched by WordPress.

Instructions
Add this to your functions.php file.

<?php
   add_filter( 'pre_get_posts', 'custom_post_type_search' );
   function custom_post_type_search( $query ) {
      if ($query->is_search) {
         $query->set('post_type', array( 'post', 'mycustomposttype1', 'mycustomposttype2', 'mycustomposttype3'));
      }
   return $query;
   }
?>