If you're prone to fatigue, you should make an appointment with your doctor to rule out potential medical problems.  Iron-deficiency, anemia, and hypothyroidism can all cause chronic fatigue and can be diagnoses with a simple blood test. If you're diagnosed with one of these disorders, your doctor can prescribe medication to lessen symptoms, including fatigue.  If you have trouble sleeping, your doctor may able to prescribe or suggest a safe sleep medication or herbal supplement to encourage sleep. Look through the medications you're currently taking and see if any of your meds may be causing your fatigue.  Many prescription drugs include fatigue in their possible list of side effects. If your dose is too high, fatigue is more likely. If you think a medication you're on is causing you to feel tired throughout the day, talk to your doctor about altering your dosage or managing side effects.  A lot of psychiatric drugs can cause fatigue. If your tiredness is so bad you're having trouble functioning in your day-to-day life, your psychiatrist may be able to switch you to an alternative med to see if the side effects are less acute. Developing good sleep habits can help improve the quality and duration of your sleep at night, resulting in less fatigue throughout the day.  Going to bed and waking up at the same time each day, including weekends, can help you fall asleep and wake up faster as your body will adapt to a schedule.  Do not use electronics half an hour before bed, as the light generated by laptops, TV screens, and smart phones interfere with sleep. Instead, try a low-key activity like reading or doing a crossword puzzle.  If your exercise regularly, make sure to time your workouts effectively. Working out within an hour before bed raises adrenaline energy and interferes with sleep.  Take a warm shower or bath before you go to bed and sip on a light tea, such as calming herbal tea, to help you wind down. Try to avoid going to bed hungry and do not smoke before bedtime.

TL;DR in Vietnamese:
Gặp bác sĩ. Kiểm tra thuốc. Thực hành "vệ sinh" giấc ngủ ngon.