There is a saying in India, "Playing the flute to a buffalo" (is wasteful), generally used in the context of knowledge imparting to a stupid person. At the end of the day, stupidity still remains. Is there an English equivalent for that?
It was first used in the Bible (Matthew 7:6), so it originally had religious overtones, but you can use it in the secular sense too:
(idiomatic) To give things of value to those who will not understand or appreciate it.
like talking to a wall
Of a conversation, completely futile due to a lack of response from another person, often because the person isn't listening.
Talking to Eddie when he's watching TV is like talking to a wall!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
- to fall on deaf ears (to be ignored or pass unnoticed)
Given that a buffalo is not stupid, per se, but only regarded as such in our environment as opposed to its own, I think the above expression is a reasonably good fit.
to do, say, or ask for something repeatedly but to be unable to change a situation
This phrase suggests the futility of some endeavor; for example, the futility of an attempt to impart wisdom to one not ready to receive it.
"The teacher told Carl to study before the test, but she was whistling in the wind."
This, and this suggest that the phrase "Bhains ke aage been bajana" points to the futility of playing a tune before an insensitive audience (I see no mention of stupidity). I would submit that the wind is at least as incapable of appreciating a whistled tune as a buffalo is of appreciating a fluted tune.
Not yet had:
Showing a dog a card trick
Both a waste of your time (and the dog's) but also implies the dog will not understand/appreciate it.
Similar but not identical: Herding cats (an impossible / pointless task)
It's over his/her head
From Cambridge dictionary:
Too difficult or strange for you to understand:
I tried to take in what he was saying about nuclear fusion, but most of it went over my head.
There may be thousands of regional variations. One I've heard is...
giving strawberries to a donkey
It's a pointless waste of strawberries which are a bit of a luxury item. The donkey won't appreciate and savour them, it will just scoff them all the same as if they were a carrot or a hand full of grass.
A lot of it depends on context. If the context is referring to an individual not understanding, Casting Pearls Among Swine might be most appropriate. If the proverbial flutist doesn't know he is wasting his time, Whistling in the Wind seems appropriate. I would offer a new phrase: If the flutist knows he is wasting time, but doing it anyway Spinning Your Wheels might be good (this is generally a reference to someone whose car is stuck in the mud, but they hit the gas anyway in a futile attempt to get out).
However, I once heard an Indian saying that could work very nicely: "Playing the flute to a buffalo"--the implications translate well to English. See what I did there.
When I was teaching in a high school, we had a principal who loved to use a phrase that has to be a very old saying from deep country. He would say, "You are grinning up a dead mules butt, boy." He would always look the person directly in the eyes and grin.
You can lead a horse to water but you can't make it drink.
(implies knowledge not actual food)
Flogging a dead horse
is used to refer to trying to make someone do something that they are never going to do in a futile attempt.
Something else that could be said:
the lights are on but nobody is home
or more appropriately
a few sandwiches short of a picnic
emphasizing that person lacks in mental aptitude