Error when I add space on the end of argument

[fluxit000]

When I make request with this url:
https://www.omdbapi.com/?apikey=API_KEY&s=game%20of%20
I get a error:

{
	"Response": "False",
	"Error": "Movie not found!"
}

but when I remove %20 on the end of s argument all working
after removing string url looks this:
https://www.omdbapi.com/?apikey=API_KEY&s=game%20of