Son Eric tested 4 commonly used search engines by using uncommon phrases from his website,  He typed in a phrase such as non-artful images and recorded what rank each search engine gave it, if it listed it at all.  So, if the phrase came up as the 4th search result, he wrote a 4 next to the search engine name.  These are the results he received:
disarming graphic content    1 Google, Lycos, Yahoo, MSN
strategy graphic content    1 MSN    4 Google    6 Lycos    0 Yahoo  {0}
language spiritual atrophy    1 MSN    4 Yahoo    6 Lycos    0 Google  {0}
literacy non-artful images    1 MSN*, Google, Lycos, Yahoo
non-artful images    1 MSN    2 Lycos, Yahoo    17 Google  {0}
perceiving very little    1 MSN    23 Lycos    28 Yahoo    0 Google  {11}
language preeminent media    1 Lycos, MSN    3 Yahoo    0 Google  {0}
descriptive content submerged    1 Lycos, Yahoo    3 MSN    0 Google  {12}
*  only result listed
{}  exact phrase search results”

HIPAA NOTICE.  Reading between the lines required.

Warning - Be careful what information you supply through the internet and how you use it.  To companies like Google and Yahoo, all internet entries are accessible.  To those who know how to use the system, information is both a commodity and power to control and manipulate.  The promise of profit and control can and is being applied to what we reveal and search for as well as to the influence of what we see and what we don't.  Google selects what articles it shows or excludes on your search, and the order of listing based on its own criteria.  This control of information includes manipulation of perceptions and gives tremendous power to whoever controls or knows how to use the system.

Ixquick advertises itself as follows: Ixquick Protects Your Privacy! The only search engine that does not record your IP address.

Your privacy is under attack!

Every time you use a regular search engine, your search data is recorded. Major search engines capture your IP address and use tracking cookies to make a record of your search terms, the time of your visit, and the links you choose - then they store that information in a giant database.

Those searches reveal a shocking amount of personal information about you, such as your interests, family circumstances, political leanings, medical conditions, and more. This information is modern-day gold for marketers, government officials, hackers and criminals - all of whom would love to get their hands on your private search data.

Why should you worry?

Major search engines have quietly amassed the largest database of personal information on individuals ever collected. Unfortunately, this data can all too easily fall into the wrong hands. Consider the following story:

In August 2006, the online world was jarred when AOL accidentally released three months' worth of aggregated search data from 650,000 of its users, publishing all the details in an online database.
That database is still searchable. It is an absolute eye-opener to see the potential for privacy nightmares.

Personal Experience - For example, when tested, Google would not display my web page by subject key-word searches, even though we registered it and did a number of other things to gain recognition.  I have conducted some searches that displayed sites at the top that didn't contain the key-words anywhere.  I have also found other sites by using the ixquick metasearch engine that Google did not display at all with the same key-word searches.  see