If you’re running a version of CentOS 6 that is a little older you’re probably running into some SSL certificate and TLS problems.  The errors would looks something like this:

[Errno 14] problem making ssl connection

Just upgrade your SSL and Certificates will help get around this issue

yum -y install ca-certificates openssl nss

Then attempt to reinstall the package from the repo that requires SSL and you should be good now.