Here's what I get in Streets 2010 using the search box in the "Search and Location" toolbar:
When I search "1800 eglinton ave e" without specifying either the city or province in the search box I get two hits, one in Mississauga and one in Toronto.
When I search "30 seneca hill dr" without specifying either the city or the province I get one hit, in Toronto.
When I enter "1800 eglinton ave east, toronto, on" in the search box I get just the Toronto selection but not the Mississauga one (makes sense when I'm that specific).
When I enter "30 seneca hill dr, toronto, on" in the search box I don't get the "Find" results box at all. Instead, it places a pushpin on the map in the correct location and has the address in the label balloon.
...ken...