Hi RamaKrishnaDatt Vuppala,
To search documents from your App Explorer, you can use the following search bar:
You can also use a shortcut for this, using Ctrl + G to open up a search window where you can type your search:
I hope that helps, regards!
Sorry it seems like I missunderstood the question.
As far as I know there is not a way to place a search bar for the navigation items. The workaround that I would suggest is to create an Entity called Page, in which you can store a string value of PageName.
This way you could store the name of the pages (as a navigation list or navigation tree would) and display them in a data container inside your layout (which should be extracted on a snippet so you can place it on the layout).
Either way, this would make a great idea to suggest using the forums. I hope that helps you, regards!