sory but i dont undesrtan woh to ''add qole's directory"

/home/user # apt-get install vlc
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package vlc is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package vlc has no installation candidate
/home/user #

are there is anothre way to install vnc?