Currently it’s not possible to filter the Events page by a certain member to see only their actions. What I can suggest as a work around that might be useful would be to use the Find function of the web browser. You can use this by pressing Ctrl+F or Command+F depending on your OS and typing in the member’s name.
I’ll make sure to pass along your comments and interest in this option to our dev team for review in future improvements to Dropbox. Sorry that I can be of much more help with this, if you have any other questions though I'd be more than happy to assist.
Have a great day - Thanks!