how do i search forums for the string "5.4.1"

Im guessing there will be a quick and easy answer for this one.
i want to search for posts with the text "5.4.1" (within body and/or subject)

enclosing in speech marks returns no results and without it treats each digit separately and does not look for the whole string of characters.
tips please. thanks to all who answer

Quote from skoczy

I go to google, enter "kemper amp forum 5.4.1" and then click on "Show more results from www.kemper - amps.com" and it results in google with quote:

"kemper amp forum 5.4.1 site:www.kemper - amps.com"

yep, that produces results, a bit more messy than using the forum search but a usable workaround.
be nice if the forum search could deliver this kind of search.
thanks @skoczy