Generating Random Numbers

I am making this small program wich generates random numbers in order to make random sums. I checked the toturial to see how to generate random numbers using the system time, wich is never the same ofcourse. The problem is that I need to generare multiple random numbers at exactly the same time.

This is a piece of code I used. It will generate differend numbers IF the user does not press enter 3 times a second..

cout<<"Strike any key to generate first value";

cin.get();

time_t x;

time(&x);

srand((unsigned int)x);

sumvalueA = rand() % (lowX-highY/lowX)+lowX;

cout<<"Strike any key to generate second value";

cin.get();

int sumvalueB=0;

time_t y;

time(&y);

srand((unsigned int)y);

sumvalueB = rand() % (lowX-highY/lowX)+lowX;

cout<<"Strike any key to generate random sum";

cin.get();

int randomsum=0;

time_t z;

time(&z);

srand((unsigned int)z);

randomsum= rand() % (randsumX-randsumY/randsumX)+randsumX;

The outcome was 3 different values when the user waited a while before pressing a key, but faster pressing a key would make the same values. :(

Is there a different way of creating random numbers, without having to use the system time??