You can't directly add multiple leads/contacts under a single company in Zoho CRM.  

However, you can follow these steps to add multiple leads:

1. Create a lead with the company name. Click on the Leads tab, select the Company field and enter the company name.

2. Create a custom field to specify that the leads belong to the same company. Learn how to create custom fields. 

3. Create a custom view to group leads which belong to the same company. Click here for more information.

4. When you convert the lead to a contact, you will get a message asking if you'd like to associate it with the existing account.

    

5. Click Convert.