As you get to the end of your PhD you might have some questions without answers. That doesn’t mean you’ve missed something. Three, four or seven years is a long time, but it’s still a finite period. You might not have been able to cover everything you wanted to.

Examiners can still be interested, and it’s likely that you are too. Make a list for your own benefit. Keep it clear. What’s your question and what got in the way of answering it?