Its Simple as abc
The easiest search quote is “index of …”
Examples are:
index of ftp/ +mp3
index of ftp/ +divx
index of ftp/ +”whateveryouwant”
Google has many operators that should help you to specify your search
USE EM
There are also lots of advanced operators available
here are a few:
cache:
link:
related:
info:
stocks:
site:
allintitle:
intitle:
allinurl:
inurl:
eg:
allintitle: “index of ftp/mp3”
Note: Try to combine things and maybe you will find something more.