metadata keywords

I use Bridge to append Metadata to the Keywords field. I would like the script below to get a a total file count of the PDFs containing ONLY the keyword "correction" on selected folders & output that info to a text file.

I'm having difficulties with mdfind & mdls. I have no knowledge on Terminal commands. Let's say I have a 4 folders with 200 pdfs each some of them have the keyword "correction" I want the final result on the text file be:

folder 1 CORRECTS= 50

folder 2 CORRECTS= 58

folder 3 CORRECTS= 115

folder 4 CORRECTS= 35

I'm just need the correct syntax code to make this work

set target_folder to choose folderwith prompt "Choose target folders" with multiple selections allowed without invisibles

set results to ""

repeat with i from 1 to (count target_folder)

set thisFolder to (POSIX path of itemi of target_folder)

--->>>> THIS iS THE PART I NEED HELP WITH -----<<<<

set fileCount to paragraphs of (do shell script "mdfind ' kMDItemKeywords == correction' -count") & quoted form of thisFolder

¬--& " -type f -iname *.pdf | wc -l"

set results to (results & "" & tab & "CORRECTS=" & tab & fileCount & return)

--->>>> THIS iS THE PART I NEED HELP WITH -----<<<<

end repeat

set theFilePath to (path to desktop folder as string) & "PDF correction count.txt"

set theFile to open for accessfiletheFilePath with write permission

try

set eof of theFileto 0

--write results to file theFilePath

writeresultstotheFile

close accesstheFile

on error

close accesstheFile

end try