Add spaces: TheElvesareinfactabouttoleavetheworldandretiretothecountriesbeyondthesea.Originally,humanscouldalsotraveltothesecountries,buttheyhaveslowlypulledfurtherandfurtherback,anditisnolongerpossibleforhumanstogetthereundertheirownpower.
The Elves are in fact about to leave the world and retire to the countries beyond the sea. Originally, humans could also travel to these countries, but they have slowly pulled further and further back, and it is no longer possible for humans to get there under their own power.