They refuse to answer, refuse so say anything. I ask again. No answer.
That's what people usually do in my lucid dreams. At first when I just get lucid, I say to them: "Hey, you are in my dream. Do you know that?" No answer. Then for an experiment I say: "Ok, if any of you are real persons, please, give me a note, my e-mail is: " and I say my e-mail ... but sometimes I mess it up :D
Then I start asking them questions, like "What is my most acute personal problem I should concentrate upon?" This does not work. Why? Because of too much control! As I know, I am lucid in my dream, my consciousness is trying hard to keep control, and this also means controlling my dream characters and trying to "put words into their mouths".
Then I found one website where some experienced lucid dreamer told a solution. He told that if a person always tries to keep too much control, he actually may lose ability to have lucid dreams, because lucidity periods will get shorter each time. He suggested to NOT control.
Concentrate on your most important question, shoot it out in your dream, and then let your lucidity go. You'll get an answer in some form or another, if you stop "being a control freak" of your dream.
Using this technique, I sometimes was able to have much longer periods of lucidity mixed with periods of a usual dream. Sometimes consciousness enters a "on/off" state - you are lucid, then initiate something (do something crazy, ask a question...) then let it go, then dream answers, and then suddenly you are lucid again ... and such cycling continues for some time, usually it's longer than a simple lucid dream.
What's also good about this technique: you can ask questions even if there is no obvious "beings" around. Ask the dream itself. There will be reaction.
For example, I asked my dream: "What is the purpose of life?" When I asked that, I was near some high building. Then I entered "observer mode". And then this building became transparent, I could see staircase now. And then stairs started to twist and finally made a circle. It was a never-ending, up-going circle. Actually like this one:http://en.wikipedia.org/wiki/Ascending_and_Descending
So maybe my dream wanted to tell me that life is a never-ending process of action-reaction, always evolving (or de-evolving). Hmm, there should be branches of various choices and probabilities ... maybe there were, but I got excited and woke up too soon.
And there is also another technique which worked for me. When going to sleep, I form a strong intent to ask some question in my dream. And then it happens like so: at some moment during a dream I start having an urge to do something important. Sometimes the dream shows me clues - one night it was a large metallic key, some other night the stars in the sky started to dance and formed some text and I had to read it. Anyway, those signs bring memory back and I do what I intended. Without even knowing I am dreaming! You don't have to be lucid to do something meaningful in your dreams. Strong intent is enough.