I always tell her that I'm calling about a certain question. The first time she read on the question. The second time, I called because there had been a material update to the situation and I wanted to get a fresh reading. She told me that she would not specifically ask the cards about it, but rather just to "look at what's coming up, understanding there's a major item of interest to you" - and she said that she expected that anything that important to me would show up in the cards naturally. She was right.
So really you're getting I guess a hybrid. I would tell her you have an item of particular interest, and what it is, and just let her do her thing. She'll proceed in the way that's best to get you a good reading. That being said, the cards won't always have a definitive answer or a final outcome for you. In my case, it simply highlighted the events within a significant period of time.