Correspondence Management using Office 365 for Mac

In my work I rely heaviliy on email to provide a record of communication s between myself (as a PM), clients and project team members. Essentially I file all emails I receive against a folder for that client/project in Outlook 365 for Mac. Each time I need to recall of reuse information in correspondence I have to search back through heaps of emails. I am wondering if there is a more efficient way I could use any tools/features in Office 365 to efficiently record and recall information that I currently hold in emails? For example is there some easy way to use say One Note, People, Planner, Delve to help?