List of fields available for expressions on Label designer

Summary:

I want to print the field: order header creation time stamp on a label but i could not able to find the right expression, o alredy try these:

strftime(\~order_header.creation_time_stamp, "%d/%m/%Y")

strftime(\~order_header.create_time_stamp, "%d/%m/%Y")

strftime(\~order_header.creation_ts, "%d/%m/%Y")

strftime(\~order_header.create_ts, "%d/%m/%Y")

strftime(\~order_header.cre_ts, "%d/%m/%Y")

None of the above works.

Can you tell were I can find a list of all fields that are availbale in label designer?

but y get "None" on my label.