I followed your link and found the page entitled Preferences. I clicked on 'Do not provide query predictions.......' (see below) then clicked the 'Save Preferences' button in the bottom right-hand corner of the page: sadly, nothing has changed. (Incidentally the URL I'm using to access Google is www.google.co.uk)
Provide query predictions in the search box.
Do not provide query predictions in the search box.
Best wishes and grateful thanks for your time.