Doc, it's been almost two month now after giving birth with cesarean operation. There's a portion of my scar that explode with water. Is that normal?

Wound seroma. No, that is not normal. You probably have a wound seroma and you should be seen by your ob/gyn. The wound needs to be drained, flushed and then packed with wet gauze (or its equivalent) and the dressing needs to be changed twice daily for up to many weeks. It will heal from the inside out and once it heals completely the scar will look the same as if the wound had not opened.
Scar fragility. Any scar which is only 60 days old is still "immature". Exploding with water is distinctly abnormal and may represent an undiagnosed "seroma", a collection of fluid, which should have absorbed. Please check with your gynecologist.