ckrahn

<h4>This plugin is an early beta version. Please don’t use it on production systems (yet)!</h4>
This plugin will give your blog access to the klickTel Open-API. 
klickTel is a brand of telegate MEDIA in germany, which provides free and paid directory listing to small and medium companies in germany. 
You can look up several kinds of information e.g. phone book entries and trade name based searches for businesses.
The intention of the plugin is to extend the existing search capabilities of WordPress to include the klickTel Open-API. 
That way you can look up directory listings for a specific search word or get the nearest restaurant to order some food.

klickTel Open-API for WordPress

WordPress Plugin to embedd klickTel Open API in your Wordpress blog

mattsgarage

The search functionality in woocommerce doesn’t search by sku by default.
This simple plugin adds this functionality search facility of your site, in both the public site and admin panel
Just install and activate – no config required.
Tested with Woocommerce 1.5.6, 2.0.7, 2.0.18, 2.2.4, 2.2.10, 3.4.4, 4.0.1 and 4.2.0
See the <a href="http://www.mattyl.co.uk/2012/12/11/woocommerce-plugin-to-search-products-by-sku/" title="accompanying blog post" rel="nofollow ugc">Accompanying blog post</a> for more information.

Search by SKU for Woocommerce

Extend the search functionality of woocommerce to include searching of sku

klickTel Open-API for WordPress vs Search by SKU for Woocommerce