Get HTML data from website in Objective-C - Parse HTML

I'm following this tutorial. It uses hpple to parse the html from a website with this code:

-(void)loadTutorials {
// 1
NSURL *tutorialsUrl = [NSURL URLWithString:@"http://www.raywenderlich.com/tutorials"];
NSData *tutorialsHtmlData = [NSData dataWithContentsOfURL:tutorialsUrl];

// 2
TFHpple *tutorialsParser = [TFHpple hppleWithHTMLData:tutorialsHtmlData];

// 3
NSString *tutorialsXpathQueryString = @"//div[@class='content-wrapper']/ul/li/a";
NSArray *tutorialsNodes = [tutorialsParser searchWithXPathQuery:tutorialsXpathQueryString];

// 4
NSMutableArray *newTutorials = [[NSMutableArray alloc] initWithCapacity:0];
for (TFHppleElement *element in tutorialsNodes) {
    // 5
    Tutorial *tutorial = [[Tutorial alloc] init];
    [newTutorials addObject:tutorial];

    // 6
    tutorial.title = [[element firstChild] content];

    // 7
    tutorial.url = [element objectForKey:@"href"];
}

// 8
_objects = newTutorials;
[self.tableView reloadData];
}

However, it seems to be outdated as it doesn't work anymore. I noticed that these lines NSURL *tutorialsUrl = [NSURL URLWithString:@"http://www.raywenderlich.com/tutorials"]; NSData *tutorialsHtmlData = [NSData dataWithContentsOfURL:tutorialsUrl]; don't work anymore. NSData is always equal to (NULL). I also tried changing the url so that is not the problem. Does anyone know how I could fix this? Thanks a lot!