Tips and tricks for IT pros deploying Copilot for Microsoft 365

I have been using 365 Chat, especially to ask questions about documents stored within a SharePoint to which I have access to. It does okay with general questions ("Summarize this document", "What are the main takeaways of this contract?"), but really struggles with more precise questions ("What is the agreed bonus on this contract?", "What are the special clauses pertaining to confidentiality in this document?"). Why is that, and do you plan on improving this? To give a comparison, using Azure OpenAI's Bring Your Own Data on the same documents works much better.