Until now, users can only create one checklist per audit, but in 3.7.4 version users will able to assign multiple checklists per audit.
In the ‘Checklist Setup’ page, you will find a new section where you can select additional audit checklist(s) for the audit (refer below images). If you add multiple checklists, you would be able to change the order of the checklists as well. You can also retrieve multiple checklist data from Global Reporting module and in the audit export.