Yes you can add s by using Add other ledger from mapping page of sales/purchase.

Steps to Follow:
Step 1. In sales/purchase mapping section scroll down the page and Click on Add Other Ledger as per shown in below image (arrow 1).

Step 2. 

1. Select Import File Header to import the required other ledgers (for example : cess, round off, discount etc) as per shown below image (Arrow1)

2. In Select Ledger select the Tally Ledger as per shown in below image (arrow 2)

Step 3. After selecting click on Save Mapping (arrow 1) and then click on Save & Proceed (arrow 2)