You can link to documents. There are two ways: 1. Start discussion from a document: Click [Discussion] on the details page of an order (PO), Proforma Invoice (PI), quotation, or inquiry. The discussion for that document will open on the right side, allowing you to review the document while replying. Both sent and received documents have this button. 2. Reference a document in a message: Click [Insert Document] in the input box toolbar, select a document to add to the message, and switch to [Timeline] view to see referenced documents. [Insert Document] can only select the sent document (original). Currently, there is no dedicated discussion entry for products. To discuss a specific product, write the product name or SKU clearly in the discussion, or use [Attach Files] to add specification sheets or photos.