Your 0% purchases are zero taxes that are included in your tax return. I'm here to share a few insights and help you from there.
First off, if you're using QuickBooks Self-Employed, this feature is currently unavailable as of this time.
Meanwhile, if you're using QuickBooks Online, you're surely able to see these options in your sale tax drop-down menu.
To start with, the Exempt (0% Purchases) are your expense which is exempt from your GST. Secondly, the Zero Rated (0% Purchases) are items/services which are taxable in special cases.
Thus said, I'd recommend checking the insights shared by @MikeinBC, on this conversation to learn more about your taxes: https://quickbooks.intuit.com/community/Sales-Tax/What-do-all-the-quot-0-Purchases-quot-options-in-t...
As always, you can visit our Help Articles page for QuickBooks Self-Employed and QuickBoks Online if in case you need to learn some "How do I" steps.
If there's anything else that I can help you with, please let me know in the comment section down below. I'll be always around ready to help.