speech delay

Hi mommies, Ask ko lang po how you deal with speech delay. How much po kaya ang check up and screening. My 4years old son on July still don't communicate. There are time na nagsasalita sya. Like mommy lets go ang pinakamahaba. Tapos daddy, eat, mikay for his cousin name. Nagblabber sya ng words pero di maintindihan. Mrunong naman sya kumanta with action, nauutusan mo pero di talag sya nagsasalita. He gets his own food when his hungry. Wents to toilet when he needs to pee and poo. Tapos he has bad temper.