Mixed invoice or proof of payment

Hello!

I can find a lot of information about claiming a percentage of mixed expenses, such as your EGW or the use of your car, which you only use partially for professional purposes. But I have a different problem.I bought some materials in the shop that I need for business, but I also bought a few items for private use. Obviously, I can’t claim the latter as an expense, but I would have liked to do so for the materials. I only have one proof of purchase (a receipt without my vAT number on it) and it lists all the items, of course…

Can I still use this receipt to claim the cost, or are you not allowed to use mixed receipts in your professional accounting?

Thanks in advance!