What is your major, and which of its requirements have you already completed?
Have you completed CSU GE or IGETC prior to transfer?
What minor are you trying to fit in, and which of its requirements have you already completed?
It looks like most majors at CSUN require about 30-50 upper division units of course work. If you have all lower division course work and GE satisfied before transfer, then you should have 20-40 units remaining of the 70 units. CSUN minors typically appear to have fewer than 20 upper division units.
However, if you need to “catch up” on lower division course work for either your major or the desired minor, or need to take more GE courses, then it may be more difficult to fit all of that into the 70 units you have left.