First of all, in order to display all Application insights, we should activate resources in the Azure PIM, for more instructions.
Then we should go to the Azure portal where all azure services should be stored
As the next step, open All services view and try to search "Applications insights" in the DevOps section through the Search.
When full list will be displayed we should choose the right app insight and it will depend on the tenant region you trying to troubleshoot/investigate.
After you clicked on the insight of the necessary region press the "Search" button and it will allow you to enter the search terms.