If you want this ability for one-off searches, you can use the OR operator.

site:http://news.ycombinator.com OR site:stackoverflow.com <query>

I don't know if there's a max # of sites you can add. I tried it with three and it seemed to work great.

http://www.google.com/search?q=site:searchengineland.com+OR+...

(Yes, I did an ego search. Isn't that the best way to know if the results are likely accurate? :)

If there's a set of sites you want to search through often, you can set up a custom search engine for what you describe. For instance, see this page:

http://www.toddnemet.com/

I've tried that [before], but with multiple parameters, I simply got zero results. I then enclosed the site:foo OR site:bar within parentheses, leaving the rest of the query outside parentheses. Whichever site:foo came first would be matched, but only it appeared to be matched. Subsequent site:bar, etc. parameters did not produce any matches in the results.

I'll have a look at your links, in a minute -- probably should have done that first.

EDIT: Well, your second link sure works. I wonder what I was doing wrong. When I saw someone else('s or s') comments online to the effect that it didn't work, I assumed that was why my own experience failed.

I'm in serious need of some coffee, at the moment. Thanks for correcting my mis-impression; I look forward to straightening it out in my mind and taking advantage of this feature.

It could be that you were using a lowercase or. It has to be all caps OR.

(lowercase or just uses "or" as one of the search terms, which I think actually is considered a stop word and is then ignored.)

And I'm always a supporter of the more coffee recommendation.

Just tried DuckDuckGo on "windows autorun". What a world of difference. Top two links are recent news, and the third link is the authoritative KB from MS on disabling/re-enabling.

I tried DDG some months (years?) ago, but it was too inconsistent. Maybe it's ready for prime time, or at least the Late Late Show, now. Jazz hands!