Bootsrap product search box like amazon

Bootstrap search box or search panel like amazon with dropdown scroll and auto adjust dropdown text based on the selected dropdown text.

Customized CSS used to make scroll bar in dropdown list

.scrollable-dropdown{
    height: auto;
    max-height:320px;
    overflow-x: hidden;
}

In above css max-height is used to specify the maximum height of the dropdown list you can increase or decrease the value or even you can further customize it based on the screen resolutions.