Rinse the jicama julienne under water for a few minutes to rid it of excess starch. In a sautoe pan or wok with a few tablespoons of vegetable oil, fry the garlic and ground bean sauce together over high heat until aromatic, 2 minutes. Add pork; continue to cook for 3 minutes. Add jicama, thick soy sauce, and sugar. Cook until the vegetables have released their juices, and the excess moisture steams out, about 10 minutes. The pan will be almost dry. Add shrimp, and cook 3 minutes more, until they are cooked through. Season to taste with salt; set aside to cool to room temperature.