If you are finding it difficult to keep track of your business receipts, consider using the QBO Mobile app to take pictures of your receipts.
First take a picture of the receipt
then click on Create (+), Expense
enter the information
at the bottom left is Attachments
browse to the picture
Save and Close.
If you have a Smart Phone (iPhone or Android), here is the BEST way: go the the Free QuickBooks Online app
click on Expense
create a new expense
click on the camera
take a picture of the receipt
enter the rest of the information