Cannot upload Arduino Nano Serail1.print to ATtiny2313

Hi every one,
After I can use Arduino Nano as ISP (Arduino 1.6.5), I had tested upload Blink sketch into ATtiny2313 via Arduino nano as ISP ,it works fine and can check voltage up/down at pin B4 or any pin that I set.

But when I use hardware TXD/RXD pin 1/pin0, Arduino 1.6.5 ,it will error on the time.

Another testing, I can upload when I use Serial.print ("xxx"); but it for usb port not pin0/1.

Could some expert / any body advise me ,how to upload serial1 port into ATtiny2313 via Arduino nano as ISP ?

My passed experiments.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Experiment1 code:

void setup() {
Serial1.begin(9600);
}

void loop() {
Serial1.print("Stuff");

}

Error : Serial1 was not declared in this scope

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Experiment2 code:

#include <SoftwareSerial.h>
// Definitions
#define rxPin 0
#define txPin 1

SoftwareSerial mySerial(rxPin, txPin);

// the setup routine runs once when you press reset:
void setup() {
mySerial.begin(9600);
}

// the loop routine runs over and over asensorpingain forever:
void loop() {
mySerial.print("Stuff");
mySerial.println();
}

Error : Sketch too big;see http://www.arduino/en/Guide/Troubleshooting size for tips to reducing it.

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Could some expert / any body advise me ,how to upload serial1 port into ATtiny2313 via Arduino nano as ISP ?

Preecha R.