For Samsung android phone.
How to remove
Step 1 : Tap and hold on the Google Search bar.
Step 2 : Drag it to the remove icon at the top of the screen.
How to retrive
Step 1 : Firstly, Tap and hold an empty space on the homescreen.
Step 2 : Tap on Widgets in the menu that appears.
Step 3 : Navigate to Google App folder and tap on it.
Step 4 : Now you can Drag and drop the google search bar from inside the folder to suitable space on one of your android phone homescreens.