Short summary
The man went to the sea to find new bottle cap. He found a wired look thing on the beach. He tryed to take it it's home hard. Finally they found the home of the lost things.
What's the main story, theme what's the lost?
I think this video explains the process of being adult. When people get old, they have to think about their future. Then they lost thier imagination. Most people are not interested in the lost thing because of this. The reason why he could see the lost thing is his childish hobby. When he found it, he was looking for bottle tops. The days with it means the life with child mind and the farewell to it means being adult. The author would send us a message that don't lose your imagination and curiosity even you become adult.
Symbol and metaphor
The city that is scarce in color = boringness
The lost things = imagination, pleasure
