Can I search for emails in the Activity Feed in Gmail?

No - Yesware's Activity Feed does not currently provide a search option. If you are looking for activity associated with a specific email thread:

• Go to the email thread by using Gmail's search bar or look for it in your sent folder
• Open the email
• Select the "Tracking" eyeball icon button at the top of the email thread to view the tracking history You can also search your Tracking Report.