There’s a difference between the thoughts you want from your supervisors before and after submission.
While finishing your thesis there are all sorts of things you might want them to consider. Does it read well? Is this right? Does it communicate what I want it to? Can you spot any typos? You want their thoughts on these and other questions because you want your thesis to be as good as possible. It can’t be perfect, but you want it to be good enough.
Your supervisors’ feedback can be a valuable part of the work that you need to do.
After submission, you still need thoughts from your supervisors but the need is different. You don’t need more ideas or suggestions on how to make your thesis better. Instead you want an outsider perspective. Your methods are sound, but what other approaches are there? Your conclusions are valid, but how else might someone look at what you’ve done? Your work is good, but what other good work could someone do in this area?
You’re not looking for more feedback. You’re looking for a different perspective. Not necessarily your examiners’ perspective, but something different to get you thinking. Listening to different perspectives as part of your prep – and responding to them – can be useful practice for the viva.