Hi Trang Nguyen 1,
 

Thanks for joining this thread. It's important that you track your taxes to ensure that the right amount is reported to the CRA. I'd encourage you to refer to the workaround mentioned above to complete this task. If you'd like to include the option to apply the HST expense on the invoice, I'd recommend that you send us Feedback by clicking on the Gear icon at the top. This is sent to our Development Team to consider for future updates. 
 

Let me know if you have any questions, I'll be happy to help.