Answer:
It shows he is trying to get in touch with the beauty and life he caught a glimpse of.
Step-by-step explanation:
Based on reading the first stanza, the narrator's adventure catching the trout was a lovely experience with nature in multiple ways. When he takes the trout home and lays it on the floor to prepare to eat it, the beauty of the experience is truly over. He's longing to recapture the beauty of that moment in nature, and will search until he is able to do so.