This article explains how to replace the native search bar in the ShopIsle PRO theme by Themeisle.
FiboSearch plugin has built-in integration with the ShopIsle PRO theme. It means you can replace the default search bar by selecting a single checkbox.
If you have activated the ShopIsle PRO theme or the child theme of ShopIsle PRO theme, you should see the following screen in the plugin settings:
Select the option
Replace all ShopIsle PRO theme search bars with FiboSearch and the search bar should be replaced.