After you are familiar with the 9001 standard, read the recent internal audit reports. Look for evidence of soft grading, such as many audits not having any non-conformances or serious problems being labeled opportunities for improvement. Soft grading can lead to external audit findings.
Take an internal auditing class if possible.
Follow-up on internal audit reports and see if reasonable actions were completed and implemented in response to nonconformances. See if the corrective actions are still used, and if not, is there a good reason why, such as a better method was implemented or data shows the corrective actions did not work as intended, in which case a different action should have been implemented. Almost always the actions need to be more than just retrain the operator.
Conduct some internal audits. Some audited processes should be selected on a random basis or because the process has not had an internal or external audit in a while. Choose a few more where there is reason to suspect possible 9001 nonconformances. But audit with an open mind and attention to what 9001 actually requires because sometimes the suspicion turns out to not be a non-conformance.
Usually, people talk about the problem areas and processes. If people talk about a process being difficult to perform, that might mean some people take shortcuts to minimize the difficulty. Find out what the known problem areas are. Look at internal audits and see how many of the problem areas people talk about have had an internal audit recently. Not all problem areas need an internal audit. Sometimes, such as an old machine that struggles to make good product, the problem is understood and may have an improvement in the works. If problem is primarily technical/engineering related rather than a failure to follow the process an internal audit may not find much. However, some technical problems are really the result of people not following the process and the requirements, in which case an internal audit is valuable. You may not know until you are done with the audit.