Doofinder

Doofinder provides fast, accurate results based on your website contents. Results appear in your search box at an incredible speed as the user types.
Doofinder can be installed in any website with very little configuration.
This extension allows you to easily populate the data Doofinder needs to be able to search your database and to insert the Doofinder layer script into your WordPress site.
With Doofinder you are confident that your visitors are finding what they are looking for.
These are some advantages of using Doofinder in your site:
<ul>
<li>Instant, relevant results.</li>
<li>Tolerant of misspellings.</li>
<li>Search filters.</li>
<li>Increases the conversion rates.</li>
<li>No technical knowledge are required.</li>
<li>Allows the use of labels and synonyms.</li>
<li>Installs in minutes.</li>
<li>Provides statistical information.</li>
<li>Doofinder brings back the control over the searches in your site to you.</li>
</ul>
When users start typing in the search box, Doofinder displays the best results for their search. If users make typos, our algorithms will detect them and will perform the search as if the term were correctly typed.
Furthermore, Doofinder sorts the results displaying the most relevant first.
More info: <a href="http://www.doofinder.com" rel="nofollow ugc">http://www.doofinder.com</a>
<h3>Requirements</h3>
Important: To use this plugin you need to have an account at Doofinder. If you don’t have one you can signup <a href="http://www.doofinder.com/signup" rel="nofollow ugc">here</a> to get your 30 day free trial period.
The minimum technical requirements are basically the same as the WordPress ones. Take a look at their <a href="https://docs.WordPress.com/document/server-requirements/" rel="nofollow ugc">server requirements</a> for more info.
<h3>Configuration</h3>
Once activated, you will see a new entry in the main menu called Doofinder with two sub-menus:
<ul>
<li>Doofinder: To access the main settings page of the module.</li>
</ul>
NOTICE: Doofinder for WordPress has built-in support for <a href="https://wpml.org/es/" rel="nofollow ugc">WPML</a>. In case you are using it, ensure you’ve switched context to one of the defined languages. In All Languages context you won’t be able to configure anything. You will have to configure as many search engines as languages you have in your site.
Doofinder Settings
<h3></h3>
General Settings
<ul>
<li>API Key: This is the secret token you use to index contents (in ML environments you can share the same key). Your API key can be found in the Doofinder Control Panel. Click on your profile name (in the header) and then on API Keys. Make sure you’re using a Management API key and not a Search API key.</li>
<li>Search Engine HashID: Id of the search engine that will index your contents. Can be found in the Doofinder Control Panel. Click on Search Engines in the header. Hash ID will be visible next to the name of your Search Engine. Remember to use different search engines for different languages if you’re in a ML environment.</li>
<li>Update on Save: The period of time that must elapse before the posts / products are updated after making a change.</li>
<li>JS Layer Script: Here you can modify the Layer Javascript Code. It is required for the Javascript Layer to work.</li>
</ul>
<h3>I have any other problem with your plugin. What can I do?</h3>
Just send your questions to <a href="mailto:support@doofinder.com" rel="nofollow ugc">support@doofinder.com</a> and we will try to answer as fast as possible with a working solution for you.

Doofinder WP & WooCommerce Search

This plugin integrates the Doofinder search service with your WordPress site.

nchankov

This plugin adding autocomplete functionality to search input field. It is using core jQuery library as well as 
autocomplete jquery plugin from http://www.pengoworks.com/workshop/jquery/autocomplete.htm
This plugin requires zero configuration, but since version 1.2.0 there is admin screen where you can enable the extra ‘number of matches’ next to each option and other goodies. 
You just need to activate and it’s ready to be used in the blog. The plugin is tested with WordPress 2.6.5, but until there aren’t big core changes, it sould work for all future releases. I don’t have 
information if this plugin will work with older versions of WordPress, but for sure it is working with 2.6.x. The last version 1.2.0 is tested on WP 2.7.1.
New in 1.3.5: When it’s selected to display posts and/or pages and the autosubmit is ON, then when the user clicks on the selected row it will go directly to the post or page url. This way user are skipping one step. The change affect only pages and posts. Categories and tags behave as now.
New in 1.3.0: Added result type option in admin. From now on you can choose which type of results will be displayed.
New in 1.2: This version could display number of matches found in the blog.
New in 1.2.1: Small fix for table prefixes and adding autosubmit once the item from the list is selected.
I would appreciate if you write an review/post in your blog with a link to my page: <a href="http://nik.chankov.net" rel="nofollow ugc">nik.chankov.net</a>. 
Thanks!
<h3>Thanks to</h3>
<ul>
<li><a href="http://nik.chankov.net" rel="nofollow ugc">My Self 🙂</a></li>
<li><a href="http://jquery.com" rel="nofollow ugc">jquery.com</a></li>
<li><a href="http://www.pengoworks.com/workshop/jquery/autocomplete.htm" rel="nofollow ugc">jQuery Autocomplete Plugin</a></li>
<li><a href="http://csixty4.com/" rel="nofollow ugc">Dave Ross</a> for the hint with name selector 🙂</li>
</ul>

Autocompleter

Adding autocomplete functionality to the blog search input field. The values provided are the tags and categories used in the blog.

Doofinder WP & WooCommerce Search vs Autocompleter