Preheat oven to 400 degrees F.
Add oil to a preheated skillet over medium to medium high heat. Saute pepper, celery, water chestnuts, onion 2 to 3 minutes. Veggies should still have a little crunch. Transfer to a bowl. Add bean spouts, crab, soy and thyme. Combine well with a spoon. Paint half of a sheet of phyllo dough with melted butter and fold sheet in half. Pile a few spoonfuls of filling 2 inches from the bottom of sheet and leaving 2 inches at either side of sheet. Fold bottom flap up and side edges in, then roll up and over until you reach the top of the sheet. Your crab pastry will look like a spring roll. Touch the edges and sides of your roll with melted butter and place roll seam side down on a pastry sheet. Bake rolls 15 minutes or until lightly golden all over in the center of the oven.