According to Osho, your forgotten questions don’t sink away; they surface from the unconscious, and when you begin to articulate them they cross into consciousness—where their repressed energy dissolves and they lose meaning, like a soap bubble. Keep writing/asking to let the unconscious empty into awareness; intellectual questions persist, but significant unconscious ones dissolve, integrating mind and transforming behavior.
Your questions rise from the hidden mind, and when you write or speak them, their power fades and they can vanish—so keep expressing them to clear the inside.