Fulltext boolean search results

[leegold]

If I search on:
BT-1034.06
I get returned:
BT-1034.02
BT-1034.03
BT-1034.05
...
BT-1034.11

If I put in "" ie. "BT-1034.06"
I only get BT-1034.06 returned.
The BT- part seems irrelevant.

But I don't understand the results.
Why so many returned? Seems like 1034.06
w/out the "" is unique enough. Is '.' a special
character and the cause? If no simple answer
I'll show you my code if necessary. Thanks for the help.
4.1.3a-beta for win32
Lee G.