Take semolina, maida, baking soda and salt in a wide mouthed bowl and mix well.
Add water in small incremental quantities and bind stiff dough.
Cover it with a damp cloth and keep aside for 20-25 minutes.
Remove the cloth and knead again until smooth texture.
Divide dough into 4 equal portions. Take each portion and give it a round shape like ball. Press it between your palms and place on rolling board.