Thanks for your reply but It didn't work. It has something to do with the block where the search box is added. If it's added inside the Cover Snippet. The dropdown list won't render outside the snipped. But if the search box is added inside the Text snippet, the dropdown menu will render outsite the Text snippet. 

I will use another snippet that allow the dropdown to be render outside it self.

Hello,

You can try with position 

.class-name {
  position: relative;
  z-index: 999;
}