You have access to your expense history on your Back Office > Transactions > Expenses.

First of all, you need to select the period you want to see on your report (placed on the top right), and then you will have: the date of each expense, the reason, the user (if any), the vat, the total amount, the payment method and the bill number. 

Remember that you have the possibility to export this report in CSV format by selecting on the top right > EXPORT