To make the dumplings, sift the flour into a large bowl. Make a well in the centre and pour in the water. Using your fingers or a spatula, draw the flour into the liquid until it has been incorporated and the dough comes away from the sides of the bowl. Turn the dough out into a lightly floured surface and knead for 5 minutes, or until it is smooth and elastic. Return to the bowl, cover and set aside for 30 minutes.
Chop the shrimps finely and transfer them to a bowl. Stir in the scallions, bean sprouts, soy sauce, wine and sugar until mixture is thoroughly blended.
Turn the dough out on to the floured surface and roll out into a sausage about 1 inch in diameter. Cut the dough into slices 1 inch wide. Flatten the slices evenly with your fingers until they measure about 3 inch in diameter.
Place a teaspoon of filling in the centre of each dough circle. Gather up the dough around the filling and bring it up over, pleating it up slightly as you bring it towards the centre. Turn the ends clockwise slightly to seal the filling in completely.
Half-fill a large saucepan or the bottom half of a steamer with water. Bring to the boil over high heat. Arrange the dumplings in a colander or the top half of the steamer, sealed side up, and place over the boiling water. Reduce the heat to moderate and steam the dumplings for about 10 minutes.