Hi Mamun!

Welcome to Steemit, I see your very new on here. In your position its very easy to get downvoted if someone dosnt look at your activity to see that you are very new user. I can give you help by suggesting to try be more human when commenting on someones post because there are many bots on here and you will be considered as being a bot and within a few days you will have forgotten about Steemit because nobody will be interested in the 3 words that you wrote.
Big love and enjoy the life!