Zoho CRM mail: Can you filter and sync only messages from customers/contacts and leads registered in Zoho CRM?

Zoho CRM mail: Can you filter and sync only messages from customers/contacts and leads registered in Zoho CRM?

Hi. 
For the Zoho integration with email. Can you filter and sync only messages from customers/contacts and leads registered in Zoho CRM?
For example. In my general email inbox I  receive customer and other email not related to CRM or my business. Some are promotional, updates from other sources etc.