Mine is the ninth edition. You can find the basics about multivariable systems in the tenth chapter. Also in ninth chapter,you can find controller design methods such as PID, phase lead or lag, notch filter, forward and feedforward, etc. Also you can find notes about multivariable systems under many control courses at MIT OCW.
Multivariable Feedback Control, by Sigurd Skogestad and Ian Postlethwaite is also a good one. More information is here: http://www.nt.ntnu.no/users/skoge/book/