Maria Daniel Deepak

WP Categories Metabox Extended extends the Category metabox on your WordPress editor. Once installed the Category metabox gets a search bar with which you search Categories. Also, this is only seen on “Add New Post” screen in the WordPress Admin dashboard.
From <a href="https://wordpress.org/support/wordpress-version/version-5-0/" rel="ugc">WordPress 5.0</a>, the search bar is included with the Categories metabox. In case you choose to use the Classic editor by using plugins like <a href="https://wordpress.org/plugins/disable-gutenberg/" rel="ugc">Disable Gutenberg</a>, then WP Categories Metabox Extended plugin will continue to extend the Categories metabox for the default “Post” post type.

WP Categories Metabox Extended

WP Categories Metabox Extended plugin allows you to search and assign Categories to your post in your WordPress editor.

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The Purpose: allowing your users to search differently
Ajaxed search engines are all over the place ? literally. 
Whenever a large amount of items is available, be it houses for rent 
or computer spare parts, providing your users with a fast, structured, faceted search 
can be one thousand times more efficient, rather than letting your visitors sink into hundreds of web pages, 
hoping they?ll find what they need ? almost by chance. 
This tool does not replace or try to extend the build in textual search feature of WordPress; 
it aims to provide a quick bootstrap to an ajaxed search engine, demonstrating how easy it can be to turn 
your website into a powerful search tool, without installing a huge and bloated code.
It is easy to hack and to extend at your will. 
You can read here the original article about why <a href="http://www.dopewp.com/searchy/" rel="nofollow ugc">Searchy</a> was built.
<h3>Main Features</h3>
Let your users search combining different criterias: Filter by name, category, tag, or custom field (=1). 
Sort results by date, name or custom field (numeric)
<h3>Typical usage</h3>
Searchy is a customizable search engine composed of two elements: the search filters – typically a filters column, and the search results.
Use the searchy_filter shortcode or the built-in widget to show the filters column. 
Place the searchy_results shortcode in a WordPress page to show the sort bar and the search results. 
Of course those go in square brackets in a chosen Page. 
You can place them one after the other, having searchy_filter and searchy_results close, 
Or get fancy building your custom layout, placing some do_shortcode calls wherever you want.

Searchy

An AJAX Search Engine allowing different criterias for sorting and filtering your posts. Use via simple shortcodes and few settings.

WP Categories Metabox Extended vs Searchy