I think your title can also read "should we blame QA for finding bugs?", to which I hope no one replies yes, although I'm not so certain about the management in your organisation.

You got it right, not all test ideas or bugs can be expected when reading documentation, requirements, or other documents. You simply have to interact with the system to come up with other test ideas that might expose other bugs.

If anyone thinks all test ideas could be figured out in advance, perhaps they can try testing for a month as a way of learning about the work. Otherwise, your only hope is to keep educating them about how testing is performed.

I think your tittle can also read "should we blame QA for finding bugs?", to which I hope no one replies yes, although I'm not so certain about the management in your organisation.

You got it right, not all test ideas or bugs can be expected when reading documentation, requirements, or other documents. You simply have to interact with the system to come up with other test ideas that might expose other bugs.

If anyone thinks all test ideas could be figured out in advance, perhaps they can try testing for a month as a way of learning about the work. Otherwise, your only hope is to keep educating them about how testing is performed.