Searching in Finder is not finding all files

The search in Finder is not displaying all of the matching files.

Test Case:

I have a folder with the following 6 files in it.

> ls ~/tmp/test

123.txt 23.txt 3.txt 34.txt 345.txt 567.txt

If I point Finder to this folder 6 files are displayed. If I enter "3" in the Search Dialog, it shows 3 files: 3.txt, 34.txt and 345.txt. 23.txt and 123.txt are not shown. IMHO the correct result is to show all files that have a 3 in them, 5 files.

I'm pretty confident that SL did not behave like this...

I tweaked the Finder Prefs, but could not get the behavior I expected.