i2c display on pro mini

Cant make the display to show somthing.
tried different resistor values from 1.5k to 10k without any luck.
have this display:
http://www.ebay.com/itm/300736978496
with this board:
http://www.ebay.com/itm/251140372362

Cant make the display to show somthing.

No code + no wiring diagram = no help.

Here is a sample code that i used:

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,20,4); //set the LCD address to 0x27 for a 16 chars and 2 line display

void setup()
{
lcd.init();
lcd.backlight();
lcd.setCursor(0, 0);
lcd.print("b2cqshop");
}
void loop()
{
lcd.setCursor(0, 1);
lcd.print('Hello World');
delay(100);
}

Here is a sample code that i used:

Assuming that the address is correct (I don't know whether it is or it isn't), that really only leaves your mysterious wiring as the issue.

i start thinking that display is defective or i2c controller on it.
it shows me black squares in 1st & 3rd line after i power it up but nothing else.
can i damage it connecting i2c vice-versa?

when i plug in display directly. bypassing the i2c it works just fine. so my guess that either i use i2c incorrectly or i2c controller on display itself might be bad

so my guess that either i use i2c incorrectly or i2c controller on display itself might be bad

Or, just maybe, you have it wired incorrectly. But, I've given up on asking you how it's wired.