The shampoo contains cleansing agents, either natural or chemical.
Choose the one that at least, or not, oil, phosphates and salt. During its action, while you massage gently, it will open the cuticles of your hair to wash them properly.
A good shampoo should contain keratin and moisturizing oils, in adaptation with your hair type, to avoid drying out and weakening your hair.
Washing your hair should be a time of pleasure, relaxation and health.