why aren't mass e-mails displayed in my sent folder

why aren't mass e-mails displayed in my sent folder

When I e-mail multiple leads, and it give me the "successful" message, where do the sent messages go?  I can't find them in my sent folder.  I need to verify WHO received them.  As it said 32 successful.  What about the other 100???  I need to locate the folder for sent mail on bulk lead blasts.  Thanks