Merge Fields from Sub form Data

Merge Fields from Sub form Data

Can't seem to work out the code for emailing sub-form data from a parent form 

I use the insert expression on the email tool,but as its variable data, its asking to define the variable (Cant seem to find a help documentation regarding this, is there way to create a email template based on all of the rows or just the latest added or as you add them

Subform: Bill Status
Parent form:  https://creator.zoho.com/kingstonscardiff/kingstons-inspection-booking-system/#Form:Bond_Status

Regards
Omar