How to fetch data from child table of another doctype Developers Print Formats

Frappe Framework Print Formats
1

Hello everyone
I want to fetch data in table in my print format from child table of another doctype.
Plz help me.
Thank you.

2

try this:
{{ frappe.db.get_value("Sales Order Item", row.so_detail, "reorder_date") }}

3

additional_coa_no = {{frappe.db.get_value(“Quality Test”,doc.name, “additional_coa_no”)}}
{%-if doc.additional_coa_no == additional_coa_no -%}

Sr
Test
Specification
Result

{% endif %}

In print format, this is my code am able to get the value in additional_coa_no but the value is not going into “if condition” can anyone able give me solution.