C-/ in completers

[Eugene C. Ciccarelli <ECC at MIT-AI>]

One thing I don't ever like is the fact that C-/ in a completing
reader does an "or" of the words you've typed so far.  E.g. if I
have typed M-Period ":draw-in-window" C-/, I will get a list of
all the definitions with ":DRAW" in them, all the ones with "IN",
and those with "WINDOW".  I can get that by trying the different
words separately just as easily, but what's more important, I
don't have any way to "and" them -- I would like to see the names
with ":DRAW-IN-WINDOW" as part of their names.

Could we either have a separate command for this, or change C-/,
or have an option variable, or something?