Import data in erpnext

while importing data into erpnext how to import two child table datas against one main table record.

Child table for a single record go one below the other, followed by the next record:

A rough outline is already present in the documentation (see section 4): https://erpnext.com/docs/user/manual/en/setting-up/data/data-import

Best way to find out? Create a couple of entries with data in the child table, and export the same.

i tried g,
But its not importing.

Give me a better solution g