The story you are referring to is a famous episode from the Indian epic poem, the Mahabharata, in which the warrior Arjuna demonstrates his archery skills by shooting an arrow into the eye of a bird.
The episode takes place during the Pandavas' exile in the forest. One day, Arjuna's archery teacher Drona sets up a test for his students to showcase their skills. He ties a wooden bird to a tree and asks each student to take aim at the bird's eye. However, before they can shoot, he asks them what they see when they look at the bird.
Most of the students reply that they see the tree, leaves, and branches, but Arjuna is the only one who replies that he only sees the bird's eye. Impressed by Arjuna's focus and concentration, Drona instructs him to take the shot.
Arjuna, with great concentration and focus, takes aim at the bird's eye. Just as he is about to shoot, Drona interrupts him and asks him what he can see. Arjuna replies that he sees only the bird's eye. Satisfied with his answer, Drona allows him to shoot the arrow.
Arjuna lets the arrow fly, and it pierces the bird's eye, striking it dead. The other students are amazed by Arjuna's skill, and Drona praises him for his exceptional focus and concentration.
This episode is often cited as an example of the importance of focus and concentration in achieving success. It is also seen as a pivotal moment in Arjuna's development as a warrior, as it demonstrates his exceptional archery skills and his ability to remain calm and focused under pressure.