Let us assume I have a website name www.mynewwebsite.com

When I open Google and search for "mynewwebsite", it lists me the website at top. But when i search for "my new website" with spaces in between I could not even see it even after ten pages of listing.

What should I do to make it work? I know that the answer is related to SEO. But is it a really big process for me to make this happen or can this be done easily?