bash - In Unix how to search string only in few files in directory -

i need grep string named "account_id" in logs folder. however, there 10000 log files there , need search in files created in last 30 days.

i need output in csv file. example

file_name       matched_string           line program1.log    account_id1         14 program2.log    substr(account_id,1,4)    45 

i did try using grep -nhi "account_id" * searches entire directory , takes lot of time

any really appreciated

directory=logs echo -e "file_name\tmatched_string\tline" in $(find $directory -ctime -30)      grep -nhis "account_id" $i | awk -f ":" '{print $1"\011" $3 "\011" $2}' done 

i'm not sure you'll output specified in question because of tab align issues

update

oneliner starts in current dir. uses find -exec , awk printf. need adjust printf format ("%-40s\t%-40s\t%-4s\n") :

find . -ctime -30 -exec grep -nhis "account_id" {} \; | awk -f ":" 'begin { printf "%-40s\t%-40s\t%-4s\n" , "file_name", "matched_string", "line" } { printf "%-40s\t%-40s\t%-4s\n", $1, $3, $2}' > out.csv