Is there such thing as unethical search engine? Yes there is. Apparently Google's search engine is biased if not politically then by your own search history. This is known as filter bubble and it makes people more arrogant and more ignorant at the same time because they see less "uncomfortable" information that contradict their beliefs. Whlist filter bubble could be useful for shopping, it is detrimental to research, education and critical thinking.

Eli Pariser's Beware online "filter bubbles" TED talk is a good introduction to the problem.

Fortunately there are alternative search engines.