In many areas of the law there are judgement calls that need to be made. This is particularly true in intellectual property where there are concepts like "fair use" running around that get settled not according to legislation, but according to precedent. As a result what seems obvious to someone who knows a little may well be utterly not obvious - wrong even - to someone with a deep knowledge of the subject. And getting legal stuff wrong can have very bad consequences. Furthermore you can be sued for misleading someone about what the law is, particularly if your advice gets them into trouble.

This is why you will find that amateur lawyers who know some of the basic stuff (ie enough to be dangerous - like me) often say IANAL (I Am Not A Lawyer). Professionals either will not give advice, or else they will tell you some generalities and then will say, "This is not legal advice." Going and giving people legal advice with the best intentions in the world can get you sued. Lawyers like being paid to put their neck on the line like that. (Or so a couple of lawyers have explained to me...)

In that spirit, IANAL and this is not legal advice. But you can have some confidence that search engines like Google have lawyers, have been through lawsuits already, and are likely to be staying within what they understand to be fair use. So if you stick within the bounds of what they are doing, you are probably going to be OK.