I have trouble sleeping

In fact, it's been a couple of nights now that I couldn't sleep well. I don't know why but I don't like what's happening to me now that I can't sleep well during the night, and I don't take a nap during the day. I find it a big problem for myself because for me to have a good and enough sleep is very important. To stay healthy and energetic for my daily activities. Certainly I am a little bit worried for myself why I have trouble sleeping and don't get enough sleep almost every night. Hopefully this problem of mine will be solved soon. But how? because I don't know what's the solution of my problem. Is there anybody can give me advice? Feel free to leave your advice and I'll appreciate it.