>I've already used its friend search function which goes through my facebook and email contacts

Not me using a completely different e-mail and name for goodreads...

>which is kinda inducing an isolated feeling,

I use goodreads as an online list of books I've read or want to read, not as social media.

This probably doesn't help you but just wanted to tell you that you're far from the only person without friends on that app.

Most people I've talked about goodreads are using it the same way I do and are ignoring all the social media side of the app