I've done interviews and classes, but am not an expert, just fairly versed in this: Most employers do not want to talk at all about money. They are looking for people who fill the nitch for the opening they have. In that, talk as much as you can about the job position and how best you can fit. When they ask you to ask questions/have questions, ask about specific job related questions, that fill that nitch and would help you fill it further. Be kind, friendly, polite, and professional. You 'can' ask about raises, promotion within the company, and furthering your career with them. Ask about their goals and how your job fits into the overall picture. Such questions are encouraged.
You 'can' talk about your need to care for family with a job-growth opportunity, etc. In other words, don't talk $$$ as much as how things relate to the job and your ability to meet the demands of that job.
If they are asking you why you want to move on, find out if they give you room to grow and advance, Then you can tell them that is the reason you are leaving, because you cannot advance and grow. They will read "more $" between the lines.
Lon