Why can't pip find packages listed in `pip search` results?

Question

First it's there:

$ pip search pylibpcap
pylibpcap                 - pylibpcap is a python module for the libpcap packet capture library.

Then it's not:

$ pip install pylibpcap
Downloading/unpacking pylibpcap
  Could not find any downloads that satisfy the requirement pylibpcap
No distributions at all found for pylibpcap
Storing complete log in /home/u0/riley/.pip/pip.log

What gives? I realize there are other ways I can install this package, but why is pip doing this?

Answer 1

This answer was meant to be a comment to J.F. Sebastian answer, as it builds on top of it, but it was difficult to copy and paste the content.

For folks who run at this problem as well and want a quick fix:

=> first, install libpcap

=> then:

sudo pip2 install http://ncu.dl.sourceforge.net/project/pylibpcap/pylibpcap/0.6.4/pylibpcap-0.6.4.tar.gz