I was speaking to the Druid today. Someone had asked him about a spell designed to gather information. The Druid told the person to consider a couple of things. First, what are the real motivations for getting the answers. The second was to consider how those answers may manifest and how that manifestation may affect others.
I am not going to go into the details of the spell but that last bit was ever so appropriate for the question being asked.
A lot of folks will just do the magick and spend very little time considering things like this. However considering them can lead to better results.
I have found that when I do thought form magick the reply always comes through the weakest point in the chain. My magick, though fiery, manifests like water by traveling along the route of least resistance. Knowing this, if I make careful consideration of what I'm doing, I can make appropriate changes. I will eschew considerations of others and use a purely practical example.
Were I of mind to do thought form magick with the intent of gaining another magickal teacher, I'd have to keep in mind the local folks I already know. Chances are one of them would show up. If I wanted them, asking them directly would be simpler. If I didn't want them, I'd have to make those 'weak' points stronger so that the magick would find another target.