For instance, one of the most commonly identified powers is resistance to radiation, and the fairer your skin, the more likely they are to identify it, because you don't get sunburned any more. And resistance to hemotoxins is identified far more than neurotoxins, because they just submit your bloodwork to test.
Meanwhile, I know her powers can drain power from people. She can then use it to heal herself or to do things she can do with superhuman capability -- run superhumanly fast, not fly. She's discovered both of these by accident. She can also shunt the power to other people to do things. (Not to heal, except to undo her draining, and not her own power -- she's going to contemplate whether it's a selfish power or her own subconscious resistance.) She has not discovered this. And I was pondering the selfish aspect, which is philosophical, and not the practical plotting sides.
Though poking at it, I can imagine at least two ways where she could learn it.