Read Wordpress extended search plugin for more information.
Wordpress Extended Search Plugin
Did you know that the default WordPress search engine isn’t really that efficient (and awesome) as the rest of WordPress?
Although the search is available as a function in WordPress, it does not search custom post types and taxonomies.
This means that if you have a custom post type as “Book” for a book review website, then the default search isn’t going to look there.
Thankfully there are a host of awesome plugins that help you implement a powerful search solution in your WordPress site, with varying degrees of specificity.
For example, some plugins help you to select search categories, whereas advanced ones enable you to search for content inside PDF files!
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Control WordPress default search to search in Post Meta, Categories, Tags or Custom Taxonomies via admin settings using WP fastest site search. Admin can select meta keys to search in, also can control the default behavior of search in the post title or post content.
Install and activate the plugin to replace the default search bar. You can customize the appearance and the search behavior from the dashboard that comes with the plugin.