In this article I am showing how to accomplish this. Flex Pro theme have slider CPT.
Step 1: Navigate to Dashboard > Slider > Add New page and change the WP Editor mode from Visual to Text. Now create a slider post and put the following HTML markup in WP Editor.
<div class="slider-search-form"> <form role="search" action="/" class="search-form" method="get"> <label class="screen-reader-text">Search site</label> <input type="search" placeholder="Type and press Enter" name="s"> <input type="submit" value="Search"></form> </div>
So Edit screen will be look like this:
Note: I directly put the HTML code in editor. But you can create a shortcode for search form and enter this shortcode into the content.
Step 2: Added some CSS in style.css file for some style. I used following CSS:
/* # Search Form on Slider
------------------------------------ */
.slider-search-form {
background: rgba(0, 0, 0, 0.55);
display: inline-block;
margin: 0 auto;
padding: 7px;
width: auto;
}
.slider-search-form input[type="search"] {
display: inline-block;
padding: 8px 10px 10px;
width: auto;
}

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