Workflow Pulling Line Items

I’ve created a workflow that creates a new invoice from a contract. The contract has line items. I can pull all the data from the contract into an invoice.

However, I’m having a problem getting the line items from the contract into the invoice.

Anyone know how to do this?

The attached screenshot is my attempt thus far. The Field -> Id, works perfect for inserting the contract into the invoice. However, this doesn’t work for the line items.

Which version of SuiteCRM is this? There were some issues recently with related modules in Reports, I believe.