How can I access my sent emails when I send them directly from the app?

Welcome to the QuickBooks Community, @useramanda-riley-yog.

Are you referring to the invoice you sent via email? You can CC yourself under the customer email box when creating an invoice so you'll see those emails you've sent to your customers. You can do this using the browser: 

1. Go to the Invoice.
2. Click the Email menu.
3. Check the Send me a copy box.
4. Enter the email in the Cc/Bcc field. 

For your reference, please see this article: Create invoices in QuickBooks Self-Employed. 

I also encourage you to visit our QuickBooks Blog site so you'll be updated about the latest news and

product developments. 

Feel free to post a reply below if you need further assistance with this. I'll be always around to help. Have a good one.