In short, you can’t. Using the following you could create and save multiple reports, one per creator, for a workaround:
Another workaround would be to use your own Creator custom field (perhaps a dropdown), which you’d have to value each time (could be required with a form) and then you could show that field as a column in an advanced search report.
The reply above which mentions my Asana2Go I’m afraid doesn’t directly offer a solution because Asana doesn’t make Created By available as a property of the task.
Larry