sharepoint online – REST API: the list cannot be found with GetByTitle ()

I'm having trouble getting lists through the REST API.
I'm calling: /_api/web/lists/getbytitle('')

I receive an error (the list does not exist) with those libraries named with more than 1 word. For example, I can't get "Site Assets." My sharepoint is in Spanish, so the titles when I call /_api/web/lists they are in spanish

I tried:

getbytitle('Activos del sitio') //Spanish Name
getbytitle('Site Assets')

I tried replacing the spaces with% 20 and x0020:

getbytitle('Activos%20del%20sitio') //Spanish Name
getbytitle('Activos_x0020_del_x0020_sitio') //Spanish Name

Tested with RootFolder.Name


I tried javascript using encodeURIComponent() with the name of the list

Nothing works. I'm getting mad at that!
Some help?

Thank you!