String QRstring = "kjrufqvbaSLIVBQERI 34685 aeonkfvbjrgq 349585";

List<String> list = QRstring.split(new RegExp(r" ")); // this will split by space

print(list);

print(list[0]); //kjrufqvbaSLIVBQERI

print(list[1]); //34685

print(list[2]); //aeonkfvbjrgq

print(list[3]); //349585