[i] Do you know any friends of hers?
[ii] Do you know any friend of hers?
The first is from a Korean grammar book and the second is mine. Whenever I come across any in questions, it’s very tricky to understand. From OALD #1, the first seems to imply that there is a set of her friends and ask if the listener knows at least a few of them. And the second question seems to ask if the listener knows her friend, whoever they are. Is my understanding proper?