Reading through the man page for tar, I don't think you can do this. If you want to extract the files from a tarfile "foo.tar", you would simply go to the directory that you want to use as a starting point and then extract it from there. For instance, if I have a tarfile named "foo.tar" in my home directory "/home/bar", and I want to extract that tar file into /opt, I would do the following:
# cd /opt
# tar xvf /home/bar/foo.tar
When you tried to do "tar xvf /data/package.tar /usr", as far as tar was concerned what you were asking to do was extract the file "/usr" from the tarfile package.tar. This may or may not have worked, depending on what was actually in the package.tar file.