the advance search button allows you to search for hits within the country specified. However, I suspect your problem is that the default google setting now is to have you use the local google server, so if you're in Australia you get the google.com.au server, if in Google UK you get the google.co.uk server.
one way around that is to use the code:
the ncr is supposed it indicate a command of no country redirect - not sure how well it works but the search page I get is google.com and not google.com.au
another is to use a VPN service like Tunnel Bear
to point it at another country. Since the browser now surfaces in another country it does the search as if from that country. So when I use google search while using tunnel bear to surface in Canada I get google.com.can not google.com.au as the search page.