We use Office 365 and their hosted Exchange for email. I manage my mail in the native Mac Mail tool; my boss uses Outlook. For commercial exchanges (ie, dialog about sales with customers), we're almost always both on copy.
SEVERAL TIMES A MONTH he asks me to find a mail for him, because Outlook search is letting him down, often on bone simple searches (e.g., for something like a specific PO number or software serial number).
I find it immediately. Outlook strikes out. How do you break search so badly?