Apsara Aruna

This is customized your search form to the full screen search box.
How to use it 
*Only you have to do after the installation, add custom link to you menu and type url to ‘#search’. you can put Link text as you wish.
Also see my other plugins 
* <a href="https://wordpress.org/plugins/widget-youtube-subscribtion/" title="Easy Subscribe Button Widget" rel="ugc">Easy Subscribe Button Widget</a> 
* <a href="https://wordpress.org/plugins/embed-page-facebook/" title="Easy Embed Page Widget" rel="ugc">Easy Embed Page Widget</a> 
* <a href="https://wordpress.org/plugins/browser-scroll-bar/" title="Browser Scroll Bar" rel="ugc">Browser Scroll Bar</a>

Easy Full Screen Search

This is customize you search form to full screen search box.

Nandakrishnan

NK Search 
Simple WordPress Search Form with Auto Suggestions
Use Short-codes to render the search form in your website
[nks] 
[nks post_type=”post-type or post-types separated with comma”] 
[nks post_type=”post-type or post-types separated with comma” class=”custom-class”] 
[nks post_type=”post-type or post-types separated with comma” class=”custom-class” placeholder=”placeholder-text”] 
[nks post_type=”post-type or post-types separated with comma” class=”custom-class” placeholder=”placeholder-text” count=”posts-count”]
It supports 
1. Custom post types 
2. Custom classes 
3. Transients to cache frequent search results

NK Search – WP Simple Search with Auto Suggestion

Custom WordPress Search Field with Auto suggestion. It can be used for custom post types.

Easy Full Screen Search vs NK Search – WP Simple Search with Auto Suggestion