Need help with Search multiple Server script

I’m new to applescript and I need a little help… I’m trying to make a script that mounts multiple servers on my desktop
and allows me to run a search for files or folders on those servers… the script works until it gets to
the search network part… then it craps out… thanks for any help…

here is the script:

mount volume “afp://172.19.98.108/johnneff” as user name “” with password “”
mount volume “afp://172.19.98.107/jcallea” as user name “” with password “”
mount volume “afp://172.19.98.97/paulhare” as user name “” with password “”
mount volume “afp://172.19.98.100/zeek” as user name “” with password “”

property search_volume : {“Plate_Drive_3”, “Plate Drive 2”, “Plate_Drive_6”, “Plate_Drive_4”}

repeat
display dialog “The Mickey Search Network:” default answer “” buttons {“Cancel”, “Search”} default button 2
copy the result as list to {search_string, button_pressed}
if the search_string is not “” then exit repeat
end repeat

tell application “Sherlock”
activate

search_network for the search_string in channel "Plate_Drive_3, Plate Drive 2, Plate_Drive_6 , Plate_Drive_4" with display

end tell