You are not able to use the Binoculars button to find words in SMTP (external) emails when the email is opened. This functionality works correctly on Windows XP but not Windows 7.
Resolving the problem
This issue has been reported to Quality Engineering under SPR MPGY8FGMU6, and currently, there are no plans to address the issue. As a workaround, you can click in the body of the opened email, and use CTRL + F to find words in the email.