All you need to do is put quotes around the phrase. Or if you want pages that must contain all the words in any order, place quotes around each word. Or just use Verbatim Search: http://support.google.com/websearch/bin/answer.py?hl=en&...

I was pleased to learn Verbatim Search no longer requires you to spend several clicks per query to use it, but sad that you cannot set it as a permanent preference.

A minimized form of a search query with verbatim enabled:

http://www.google.com/search?tbs=li:1&q=britney+speers

Edit the search engine definition string in your browser to something like that...