Asset Merge

Hi Experts,

Scenario: I have entered an Invoice with two lines i.e. Asset line and other is the tax line.

After running the mass Addition I see two asset lines in Fixed Assets.

The tax line gets automatically merged with the asset line ?

My question is 'Is there any setup to do so'? How does the system automatically merge the tax line with asset line, wherein when I

take two different asset line on the Invoice, after running the mass addition i find two separate asset line both with 'NEW' status.

Any help will be highly appreciated

Thanks in advance