I think the problem most students are facing is too much information on the net.
For example, if your assignment for them is to figure out the Impact of 2008 financial crisis to GM.
If they google for "2008 financial crisis GM", they would get about 4,030,000 results.
The first one on the list is, Scholarly articles for financial crisis 2008 GM. If you click on that, you get 300,200 results. Do you expect them to read through all of them? I don't believe so.
I believe most undergrad student today do know how to search. But, they may have trouble with filtering them out because of the large volume of info they get on Internet.
In order to help them, you need to figure out how much time it would take them to find the info you want them to find, assuming they would do the search themselves.
In other words, you need to do the homework first. Pretend you know nothing about the subject. Search on the net. Find the info yourself. If you can do it in a reasonable time, then you can expect them to do it.
Using the example above, I cannot find the document you want me to find in a reasonable time frame unless you tell me specificly what you are after.
The line you want really depends on the assignment and student's willingness to learn. I don't think typing keywords is a problem, how to choose keywords and what to do after the search are what's troubling them.