Validation rule

Hi Guys I'm trying to amend the following validation rule which currently throws up an error where a GL'A Account Tagged as product required is TRUE and the product field is blank

AND(c2g__GeneralLedgerAccount__r.Product_Required__c =TRUE,  ISBLANK( c2g__Product__c ))

What I'm trying to include:

I'm trying to amend the validation rule to ignore this validation where the journal line description is Revenue Revenue recognition Journal or Reference begins with RT-

Can someone please help we with how I can amend the validation to include these new conditions?

Thank you

Temi