Hamburger menu -> customise -> drag the search box onto the toolbar. Cmd + k (on mac at least) will focus it ready for your search.

I have a separate search and address box! It doesn't change the behavior.

If you have a bookmark "Hello World!" pointing to "example.com" and type "Hello" the selected option will be "Search with Google" and not the top bookmark entry.

I remember when that used to be the default and then Chrome came along with the omnibox and changed the game.