If I want to search for a phrase in the SDMB, do I put the phrase in quotation marks, , ( ), or do nothing other than type it? Or what?
Quotes. 
Actually, you can’t do phrase searches. The search engine is so simpleminded that if you enter, say,
“search engine”
you’ll get back all of the threads which contain both the string
"search
and the string
engine"
In other words, it treats “special” characters (other than spaces) such as quotation marks just the same as it treats letters, digits, or any other characters. If your phrase contains more than one unusual word, you can just enter the individual words and hope for the best, but they’re not guaranteed to be in the same phrase, or even in the same post.
If you’re looking for a specific thread, it also helps if you can remember the name of one (and ONLY one) poster who posted to it, as well as a few words used in topic lines in the thread.