Rank order of search results

[mdub]

Dear Users:
Does anyone know how to manually change the rank order of search
results when first typing into the QS window (after cntrl-space)?
I type "fire" and firefox-parallels comes up first in the list with
firefox in os x second. If I accidentally press return, parallels
starts. Does anyone know how to change the order so that firefox under
os x comes up first?
Thanks in advance!
Marc