"Lord Jesus, in Your awesome Name, if Marthin is alive, please let him be found safely. If he is scared, please comfort him. Please show the searchers where he is, Sir. And please be glorified in this situation, no matter what the outcome. Amen".
Also, Medolina, in the area where I live, when a child is missing, they usually use dogs to try to follow the scent of the child. I don't know if dogs are trained to do that in Kupang, or if it is even possible after a flood (perhaps all the scent is washed away; I'm not sure), but it's worth looking into.