If you want the old stricter Google behavior be sure to check the "Verbatim" option under 'tools', or add "&tbs=li:1" to your uri. Around 2008 Google started testing a new search engine logic, codenamed caffeine?, which eventually became the default. Without being sure, I think verbatim uses the old engine which wasn't trying to be smarter than you and your query, certainly is stricter and reminds the old Google a lot.