How to use find to get only string sequence, not within other words

I've not found a way to get Preview to search for characters like # or +, but Skim, an alternative PDF viewer (homepage here), is a good replacement/addition to Preview and is able to search more specifically.

I've tested it and found it was able to find C++ (without needing any quotes/special options) without bringing up all C results.

It was also able to search specifically for accented characters (like é or ö) — though requires such characters to be accented in the search to find them (i.e. you can't search for blah and expect it to match bläh, nor vice versa). In Preview, either search will return matches for both accented and unaccented characters.

There are a variety of ways of searching for a file by name. I'd just open the Terminal and run locate xxxxxxxx-xxxxxxxx, although the locate index is only updated once a week, so if it's a new file it might not be listed. If you want, you can manually force an update with sudo /usr/libexec/locate.updatedb (you'll need to enter your admin password for the sudo).

You can use Spotlight in the Finder, but it leaves out system files by default -- there's a way to change this, but it's a little complicated and may not be the same in 10.4. (EDIT: instructions for doing this in 10.6 are in Apple's KB #HT4355.)

Finally, you could use the find command: sudo find / -name xxxxxxxx-xxxxxxxx -- this will require your admin password for the sudo, and will be slow (it actually looks at all your files to find a match), but should find things the other options might miss.