Check one time below code...
At place of dict use your dictionary which containing the data:
NSString *strid = [[dict objectForKey:@"Fact tags"] objectForKey:@"fields_id"];
NSLog(@"str = %@", strid);
or you want get the list complete dictionary use the code but you have to assign value to string or wherever want.
NSString *str = [NSString stringWithFormat:@"Fact tags\nfields_id=%@\nfields_list=%@\nposm_details=%@", [[dict objectForKey:@"Fact tags"] objectForKey:@"fields_id"], [[dict objectForKey:@"Fact tags"] objectForKey:@"fields_list"], [[dict objectForKey:@"Fact tags"] objectForKey:@"posm_details"]];
NSLog(@"%@", str);