Hello, this is my first time using a 3d printer. I had just purchased the SV03 and was following the instructions for leveling. I started off with the leveling corner option and notice there was quite a large gap between the a4 paper and nozzle. I have tightened to the max the bed adjusters and still got the result below. When I tried moving the z offset, no matter what number I changed it to the nozzle did not move. Sorry for the blurryness but I could not get my camera to focus. That white is not the bed but the a4 paper I placed.

Hi eunjul,
if you turn the bed leveling screws in the opposite direction it will loosen the screws that hold the springs & move the print bed upwards. This will minimize the gap between nozzle and print bed.