account.move.template.line.tree account.move.template.line account.move.template.line.form account.move.template.line

You can refer to other lines using their sequence number e.g. L1 for line with sequence = 1. Examples:

L1 * 0.2
L2 - L1
L1 + L2 + L3
1250

account.move.template.form account.move.template account.move.template.tree account.move.template account.move.template.search account.move.template Journal Entry Templates account.move.template tree,form