WordPress :: Divi Builder :: Search Module :: Custom Post Types

child-theme-functions.php

<?php

function my_remove_default_et_pb_custom_search() {
	remove_action( 'pre_get_posts', 'et_pb_custom_search' );
	add_action( 'pre_get_posts', 'my_et_pb_custom_search' );
}
add_action( 'wp_loaded', 'my_remove_default_et_pb_custom_search' );

function my_et_pb_custom_search( $query = false ) {
	if ( is_admin() || ! is_a( $query, 'WP_Query' ) || ! $query->is_search ) {
		return;
	}
	if ( isset( $_GET['et_pb_searchform_submit'] ) ) {
		$postTypes = array();
		if ( ! isset($_GET['et_pb_include_posts'] ) && ! isset( $_GET['et_pb_include_pages'] ) ) $postTypes = array( 'post' );
		if ( isset( $_GET['et_pb_include_pages'] ) ) $postTypes = array( 'page' );
		if ( isset( $_GET['et_pb_include_posts'] ) ) $postTypes[] = 'post';
		
		/* BEGIN Add custom post types */
		$postTypes[] = 'product';
		/* END Add custom post types */
		
		$query->set( 'post_type', $postTypes );
		if ( ! empty( $_GET['et_pb_search_cat'] ) ) {
			$categories_array = explode( ',', $_GET['et_pb_search_cat'] );
			$query->set( 'category__not_in', $categories_array );
		}
		if ( isset( $_GET['et-posts-count'] ) ) {
			$query->set( 'posts_per_page', (int) $_GET['et-posts-count'] );
		}
	}
}

Cool! Thank you very much as it worked for me. Although it doesn't search in the custom fields data. Do you know how to make it able for searching within custom fields?.

////// UPDATE

I've found this very useful explanation and snippet code for achieving what i've requested: http://adambalee.com/search-wordpress-by-custom-fields-without-a-plugin/