This plugin adds Spotlight ™ like live search with an ajax popup to 
the default search box. See the screenshot.
It can be used as a widget or directly as a PHP call in the theme.
The Live Search Plugin is heavily based on John Nunemaker’s 
<a href="http://www.wp-plugins-db.org/plugin/addicted-to-live-search/" rel="nofollow ugc">Addicted To Live Search</a>.
<h4>Changelog</h4>
<ul>
<li>1.4.7 Fix by Tony for “With mouseover on result in IE, there is no background image or color”.</li>
<li>1.4.6 Added livesearchpopup_resultsbox(width) to put the popup below a search box of your choice, e.g. from a theme.</li>
<li>1.4.5 Do not initialize if no livesearchpopup_results is found. In contrast to the original live search this plugin does not make sense without the popup anyway. This fixes a JavaScript bug in IE7.</li>
<li>1.4.4 Use wpurl instead of siteurl to allow installations of WordPress at different addresses (thanks to Draco)</li>
<li>1.4.3 Use <?php instead of <? in live-search-popup.php</li>
<li>1.4.2 Force update script to update the plugin.</li>
<li>1.4.1 Switched to the_post instead of the deprecated wp_start().</li>
<li>1.4 Finally permalinks work together with this plugin. In addition a “Show all” links was added at the bottom for the case that there are more posts than shown in the popup (thanks to Marco Luthe).</li>
<li>1.3.4 Moved the placeholder and autocomplete attributes of the search box to JavaScript as they are not XHTML valid (thanks to Marco Luthe)</li>
<li>1.3.3 Added some print commands in front of get_bloginfos (thanks to upekshapriya who noticed that)</li>
<li>1.3.2 Force update script to update the plugin.</li>
<li>1.3.1 Relative paths in css to allow installation which are not at the domain root.</li>
<li>1.3 Fixed behaviour for change and blur events of the search box. This fixes the “click-through” bug.</li>
<li>1.2.1 Updated to reflect that it works with 2.3 as well.</li>
<li>1.2 Bugfixes</li>
<li>1.1 Bugfixes</li>
<li>1.0 First release</li>
</ul>

Live Search Popup

Spotlight (tm) like live search with an ajax popup

Konstantin Obenland

This plugin lets you provide the user with search suggestions based on the information entered in the search field.
It adds an AJAX call to the search form, returning matches for the current search query from the database. 
There is no change of template files necessary as this plugin hooks in the existing WordPress API to unfold its magic.
<h4>Translations</h4>
I will be more than happy to update the plugin with new locales, as soon as I receive them! 
Currently available in:
<ul>
<li>English</li>
<li>Deutsch</li>
<li>Czech</li>
</ul>
<h3>Filter Reference</h3>
wpss_search_query_args (array|string)
<blockquote>
The query args, passed to <a href="https://codex.wordpress.org/Function_Reference/WP_Query" title="WP_Query in the WordPress Codex" rel="nofollow ugc">WP_Query</a>, either as an array or a string. 
 An array with the default query args and the current search query are passed to the filter.
</blockquote>
wpss_search_results (array)
<blockquote>
An array with the result strings as values. An array with the default results and the WP_Query object are passed to the filter.
</blockquote>

WP Search Suggest

С плагином интернет-магазина WP Shop работает отлично.

Чтобы саджест-поиск не искал в ненужных типах записей в файл functions.php достаточно включить функцию-фильтр, в которой настроить WP Search Suggest под себя:


    `/*
    * Customize plugin WP Search Suggest
    */
    function wp_search_suggest_custom($query_args) {

        $query_args += [
            'post_type' => ['post', 'page'],
            'posts_per_page' => 10,
        ];

        return $query_args;
    }
    add_filter( 'wpss_search_query_args', 'wp_search_suggest_custom');`

Отличный плагин для поиска по товарам с подсказками

I like this simple Plugin, I only would wish to have more results or to set an option for this ;)

Simple is the Best!

Great and clean plugin!

Provides title suggestions while typing a search query, using the built-in jQuery suggest script.

Live Search Popup vs WP Search Suggest