Send POST request in Objective-C - objective-c

Question

I need to send a POST request to a website to load more results of the page (There is about 200 results that I want to parse (using TFHpple) but the page is showing just 40 and you need to click "Show More Results" at the button to load more (there is 4 pages))).
Every time one or two addresses are different and the other is the same, why is it? All of them should be different.
I tried to search the web how to send a POST request and I tried but it hasn't succeeded :( Can anyone help me figure it out?
General information:
Remote Address:212.117.156.55:80
Request URL:http://www.d.co.il/DOTNET/ajax/GetMoreResults
Request Method:POST
Status Code:200 OK
File Name: GetMoreResults
If there is any additional information required, just write in and I'll give you it.
Thank you very much!
Am I done this right?
NSURL *url=[NSURL URLWithString:#"http://www.d.co.il/SearchResults/?query=%D7%A9%D7%95%D7%A4%D7%A8%D7%A1%D7%9C&type=tag&location="];
NSData *data=[NSData dataWithContentsOfURL:url];
TFHpple *parser=[TFHpple hppleWithHTMLData:data];
NSString *XpathQueryString=#"//p[contains(#class, \"result-contact-address\")]";
NSArray *Nodes=[parser searchWithXPathQuery:XpathQueryString];
for (int i=0; i<4; i++)
{
NSError *error;
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:nil];
NSURL *postUrl = [NSURL URLWithString:#"http://www.d.co.il/DOTNET/ajax/GetMoreResults"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:postUrl
cachePolicy:NSURLRequestUseProtocolCachePolicy
timeoutInterval:60.0];
[request addValue:#"GetMoreResults" forHTTPHeaderField:#"Content-Type"];
[request addValue:#"GetMoreResults" forHTTPHeaderField:#"Accept"];
[request setHTTPMethod:#"POST"];
NSDictionary *mapData = [[NSDictionary alloc] initWithObjectsAndKeys: #"80", #"batchNumber",
#"IOS TYPE", #"typemap",
nil];
NSData *postData = [NSJSONSerialization dataWithJSONObject:mapData options:0 error:&error];
[request setHTTPBody:postData];
NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
}];
[postDataTask resume];
}
int i=1;
for (TFHppleElement *element in Nodes) {
NSString *address = element.text;
NSLog(#"%#,%d",address,i);
i++;
}