Can you share some specific examples from the Satcharita where Udi was used to heal people?

Yes, Chapter 33 of the Shri Sai Satcharita contains a footnote with several powerful examples of Udi's healing power. One story concerns the daughter of Khimji Lalji Joshi, who was so frail she could not walk. When she was brought to Shirdi, Sai Baba applied Udi to her, and within a few days, she began to walk again. Another account is of a friend who had suffered from insomnia for eight days; after taking the Udi for just one night, he was able to sleep soundly. A third instance mentioned in Chapter 33 involves a child who hadn't slept for two months. After his father took him for Baba's Darshan in Shirdi, the child began to sleep normally from that very night, demonstrating Udi's profound effect on various ailments.