During parent-teacher conferences, the teacher has only 20 minutes to go through everything the school requires them to cover (grades, milestones, whatever) and there's usually little or no time left for meaningful communication. One can only stretch the time so much before destroying the schedule (which parents make the effort to arrive for), so the teacher does it for the students who most need some sort of change.
So, the short answer is "don't expect anything meaningful from parent-teacher conference day". It's simply impractical given the format.
What you can do to get meaningful feedback from the teacher is to have contact frequently outside of the once or twice-yearly conference. Write a note, send an email, catch him/her at a school event. When you do communicate with the teacher, make sure to:
Have specific questions, and offer specific, concrete examples of anything that concerns you or goals you want to help your child reach. (If you don't want a boilerplate response, getting boilerplate questions to ask isn't the way to go.)
Make communicating with you as lightweight for the teacher as possible. Do what is convenient for him/her. You have one or a few kids to worry about -- he/she has dozens. Respect the teacher's time and he/she will notice.
Make sure the teacher has a chance to feel you out over several different occasions. A teacher can't give you information you will find valuable unless he/she understands what your parenting style is, and how you react to different types of presentation.
Finally, understand that not all teachers are big on parent communication. Some are just jaded, some can't be bothered, and others have bought into the social pressure against seeking to "fix what isn't broken" by looking for ways to enhance the education of students who aren't struggling.