Hi Dmitry,
Thanks for your reply.
I have customized the Azure search index and now it's returning the sys_content field. However I'm still having issues filtering the content that's in the field. I want to exclude the "DocumentWebParts" field from the sys_content.
The DocumentWebParts searchfield doesn't exist when using the param in the CreatingField > Before event. Do I have to modify this in a different event?