Before you could cancel auctions anytime, you could infer if an item had been bought.
Make a search to that shows it.
Make the same search later, if the item is no longer here, it has been sold!
For example: you search a ring that is at 2h23min remaining time. 1 hour later, you perform the same search and the ring is not here: it has been sold.
Now that you can cancel any auction anytime, you can not be so sure. The only sure way to know what people are willing to pay for an item is to watch auctions : you know a minimum amount that the item will sell for.
I am asking that to better know the market and not being fooled by overpriced items.
Best Answer
No, there is no way to know for sure if an item has been bought from the auction house.