Try clicking the More Help link under the search box. It explains how to do advanced searches.

http://www.rcuniverse.com/searchhelp.html

The idea with a powerful search is to not have to do much more then put in your terms and we find them.

If you need to narrow by forum, date, username just click the narrowing filters on the LEFT side of the page

There is no comparison of this search to the old one. It is like comparing a Yugo to a Ferrari. Our #1 complaint on RCU the last 3 years running was bad forum search. Maybe a few of you liked the old one and if so you can bookmark it at your own peril. When it doesn't find what you want try the new one. It will.

Minnflyer: username is supported. just type username:"user name here". Also the drop down suggestions will find usernames for you now. Type in minnflyer and watch your name appear. THEN just type 'username:' before your name so it shows as 'username:minnflyer' and click search.

We do not have dropdowns so you can actually make this powerful. Say you wanted to search for a word in the subject, another word in the body and by username you simply could type for example "subject:falcon body:56 username:minnflyer". You can make it as easy or build as complex set of rules as you want

Also I just added quick click to find posts by user. In any post you see they have a post count. that is a link to instant search for all their posts. You can then narrow by date, forum or add keywords to it to search for something specific by them. All < 1 second results too.