XML : How to solve the error ":37: parser error : EntityRef: expecting ';'" in Xcode, Objective-C

I tried the Xcode Project which gets RSS and view the articles from the websites. https://github.com/icanzilb/Advanced-RSS-reader

But I can't get the articles from some websites.

And the error

" :37: parser error : EntityRef: expecting ';' "

and

" * Terminating app due to uncaught exception 'NSRangeException', reason: '* -[__NSCFString substringToIndex:]: Index 100 out of bounds; string length 77' "

have caused. How can I solve this errors?