Well configured on-site search is absolutely crucial to the user experience, and with WP Extended Search you can configure the native WordPress search to your hearts content. If you use WooCommerce, you can include (or exclude) product category, tags etc, and if you add other custom post types or fields, there is no way around fine-tuning search to include those fields. The greatest thing about WP Extended Search is that it tweaks the native search functionality, and it’s thus compatible with whatever theme it’s used in combination with.
Extract from WordPress.org
With this plugin you can customize WordPress search to search in Post Meta, Author names, Categories, Tags, or Custom Taxonomies via admin settings. You can control the default behavior of WordPress to search in the post title, post content, and post excerpt.https://wordpress.org/plugins/wp-extended-search/