Not able to save multiple objects using nskeyedArcheiver - objective-c

Question

I am trying to use NsKeyedArchiever to take save Car details which contains model,make,year,color,vin.
The code for this is as follows :
void CarData()
{
Car *myCar = [[Car alloc] init];
myCar.model = [carTempArray objectAtIndex:0];//Temporary array contains value
myCar.make = [carTempArray objectAtIndex:1];
myCar.color = [carTempArray objectAtIndex:2];
myCar.year = [carTempArray objectAtIndex:3];
myCar.vin = [NSNumber numberWithInt:check];
NSString *docspath = [NSHomeDirectory() stringByAppendingPathComponent:#"documents"];
BOOL saved =[NSKeyedArchiver archiveRootObject: myCar toFile:docspath];
NSLog(#"did save state %d",saved);
[myCar release];
[NSKeyedArchiver release];
}
And after that using NSkeyedUnarcheiver as follows :
void ShowData()
{
NSString *docspath = [NSHomeDirectory() stringByAppendingPathComponent:#"documents"];
Car * retrieveCar = [NSKeyedUnarchiver unarchiveObjectWithFile:docspath];
// for(int i=0 ; i<studentList.count;i++)
{
// Car * retrieveCar =[studentList objectAtIndex:0];
NSString * first = retrieveCar.model;
NSString * first1 = retrieveCar.make;
NSString * first2 = retrieveCar.color;
NSString * first3 = retrieveCar.year;
NSLog(#"%#",first );
NSLog(#"%#",first1 );
NSLog(#"%#",first2 );
NSLog(#"%#",first3 );
}
But this only takes one value and uses one value.I want to save the NSKeyedArchiever object in an array so that multiple cars can be a part of it using same code.And Load the same as above.Please rectify the problem .I want to run the code for multiple cars and i am able to perform the following tasks in array of cars as searching a car,deleting a car record and adding a car.