Since I don't know this particular story, it might be a story that is specific to a certain community or area. It could be about a relationship between a Kabuliwala (someone from Kabul perhaps) and a Bengali woman. But without more information, it's hard to tell the full story.
It could potentially be a story about identity. The Kabuliwala may have his own identity shaped by his Afghan origin and the Bengali bou by her Bengali culture. Their story could explore how they maintain or change their identities while being involved with each other. Also, it could touch on themes of acceptance, where they either accept or struggle to accept each other's differences.
I'm sorry, I'm not familiar with the specific 'kabuliwalar bengali bou' story. It might be a relatively unknown or regional story. You could try to find it in local libraries, ask local storytellers or search in specialized Bengali literature resources.
As I don't know the story, I can't say for sure. But likely the main characters are the Kabuliwala, who might be a trader from Kabul with his own cultural background and way of life, and the Bengali bou, who would represent the local Bengali culture and traditions.
Unfortunately, without more context, it's difficult to provide the full story of 'bou kotha kou'. It could be a name of a story within a small community or an emerging piece of literature. If you could give some more details like where you heard it from or what kind of story it is (e.g. a love story, a mystery) it would be easier to answer.
One way is to visit local libraries. Librarians can be very helpful in guiding you towards family - friendly Bangali literature. They can recommend books based on your interests, whether it's about Bangali history, traditions, or just good - hearted fictional stories.
There should be no so - called 'bangali sex audio story' for educational purposes. Educational content usually focuses on positive knowledge, culture, language learning, etc., not on sexual - related stories which are inappropriate in an educational context.