In Zendesk Support > Add the ability to create subviews
Currently, zendesk doesn't have subviews feature out of the box.
Please check the Apps marketplace for existing apps that allow you to organize views as a subview
I have described the View categorization (subviews, dropdown view) in detail and explained the benefits of it.
Please visit my article (below) and vote for it if you think that it would be beneficial for you too!