How come in Finder, when I search "This Mac", there's fewer results than when searching somewhere more specific? Shouldn't it be the opposite?

Question

I have my preferences set so that New Finder windows show Macintosh HD. So when I open a Finder window, five folders are shown: Applications, Library, System, User Information, and User. As an example of the subject of my question, I opened a Finder window and typed "hp" in the search field. Four results were displayed: HP ePrint.app, two other apps that open the printing queues of HP printers, and an HTML document of bookmarks with two bookmarks containing "hp" in their names. My goal of the search* was to find a folder named "hp", of which there are two that I know of on my computer. Their locations are: 'Macintosh HD/Library/Printers' and 'Macintosh HD/Library/Application Support'—neither folder was found when searched for in "This Mac" nor when searched for in "Macintosh HD". When I searched for "hp" in the Library folder, 36 results were displayed, including the two folders named "hp". Above those 36 items, it clearly indicated that my search was conducted in the Library folder, and that I was able to click "This Mac" to search my whole computer instead. Clicking "This Mac" resulted in the same four items that were found when I searched for "hp" immediately after opening the Finder window to be displayed again. In my mind, clicking "This Mac" should at least keep the 36 items found in my Library folder to remain displayed. My reason for thinking this is because the Library folder is contained in "This Mac", isn't it? The same logic applies to Macintosh HD also; why doesn't searching there return at least the same 36 results? This phenomenon of the contained location returning more search results than the location which contains it frustrates me. When I search for something, I have to guess if it's in Library or System (if it's in one of the other folders, I'm always certain of which to search). I know that doesn't seem like a big deal, it just doesn't make sense to me why I can't find things by searching in "This Mac" or Macintosh HD. Until I got this MacBook (15" Pro Retina mid 2012, 2.6/16/256) , I was a lifelong Windows user. I love my MacBook, but this search idiosyncrasy is the only thing about it that seems inferior to its Windows counterpart. Searching for something in Windows is easier to me because locations behave hierarchically. I still like my MBP way better than any other computer that I've ever owned before, I just wish Apple would change this one attribute. If anyone knows how to make the Finder search behave completely hierarchically (when the containing location returns at least the same search results as the location it contains), please let me know. Thank you.
*The "hp" folder search that I conducted was done only as an example of the issue that I discussed here. I knew where the folders were, thus, it was easier for me to explain the problem that was posed in my question.

Answer 1

Start with http://www.pinkmutant.com/articles/Leopard/leospot.html and http://www.thexlab.com/faqs/stopspotlightindex.html, then my mod to Finder's Find at http://www.macosxhints.com/article.php?story=20080229204517495 for what you can change so you can find stuff excluded by the default structure.