How to identify good and bad friends?

If your eyes see some of your friends with bad qualities then most probably they have some crazy doubts in their heads means no clarity. And they may still not find anyone talking about their doubts & beliefs and discuss the truths with clarity. It’s like the impure water. Everything is open in this universe, so we as water are living in this universe openly. So the water may contaminate by any means of external factors. But we know from our consciousness that water is totally pure by nature. So it depends on the effectiveness of the filtration process to revert the impure water into its true pure nature.

Now resemble this impure water with a friend of yours with some bad qualities. But you know that both the water and your friend are pure by nature. So now it depends on you how much clarity you have in the truths you know well so that you can influence your friend for good!
This will improve your two things: real life problem solving and effective communication skill!