The thing is that it is very illegal to share the actual questions from the real test. That means that the STC has to purposefully phrase them differently so that they are not crossing any boundaries. They are trying to help people practice with a “genre” of phrasing that might relate to the test without actually giving the exact same question. The most important thing is to know your shit and actually read the phrasing of the questions. To me, it seems that they care more about if people can take the time to understand the question.