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I will try to present yet another approach than the ones in the answers above. I don't consider it a definite solution, rather a way to go that may work for someone and may not for someone else. (And also, I would much more prefer to speak to someone higher-up, if you can; that's what the other answers discuss.)

The thing is: Be honest, but without judging the other person's qualities at all. I had been in such a situation before: person coming to me with simple problems that fall in the "googlable" or "in every book" or "in every course" or "in every tutorial" category, again and again.

The honest answer was, for me at least: Well, we have discussed a similar thing before. I'm sorry but I have got other things to do as well. I'm willing to help you with the burdens, but please, try to [point out some good resources here] before approaching me, and if you approach me, please make it specific enough so that we don't lose too much time solving the problems.

It is true, honest but not rude. After all, it is your time, your studies and you yourself who'll go on the market to sell your results, and you need to be productive. If this is a serious annoyance that makes your productivity drop significantly, they need to know it.