DuckDuckGo: is there an advanced search or search engine features?

Question

User interface

Good time to you. I have a somewhat blurry question, but I think it will be clear to you. Interested in
usefulness in the DuckDuckGo search line.
For example, if I enter in the address bar: qr toster.ru
The issue will be with the QR code of the toaster address.
That's it.
I wonder if there are any other useful things that can be used from the address or search bar.

Answer 1

There are many articles on this search engine. For me, the most important thing about it is the ability to manage the relevance of the search. For example - search by personalities.

Answer 2

There is also a search through the search lines of sites !bing <query> and so on !winehq <query> is also interesting.