help with taking input from body

I would like to match a subject "search_archive" and take the body  
and filter it through a 'for' loop

the format of the body would be like this

somestring
someotherword
thirdword
fourthword

I would like to use the body like this

for i in somestring someotherword thirdword fourthword
do
        grep $i file
done

there could be ANY number of lines in the body of the message


Is this feasible?

I have no idea where to begin


TjL