I like the way Eudora handles this. After your search, In the search 
results window is a checkbox for "Search results." You simply check 
the box and enter a new term in the original search field. Perhaps 
"Search these results" would be more clear.

1. One active box, to avoid having to label, explain, error, etc.

2. If you want your first term to persist you could simply display it 
or display it in a grayed-out inactive field and the new field could 
pop into view as the checkbox is checked, next to it on a new line.

3. In Eudora you can't. You have to redo the initial search. It's 
easy and fast though.

If I were to design one today I would probably use a Back button 
(left-pointing arrow) since those are well understood in browsers 
now. It could re-do the search for the user. If your search engine is 
slow, perhaps you could cache the results instead of re-searching.

I find I generally search, search within, and if I get too few 
results, I want the initial results again, to re-do a search within 
using a new term. So keeping the search-within results handy is not 
useful, but keeping the original results is.

Note that Google accomplishes this search-within trick by simply 
adding term 2 to term 1 in the search box. If that would work for 
your search engine, you could teach users to do this by showing them 
the query string in the first box as it is altered to use the second 
term. They could widen their search by deleting any operator and the 
second (or third, etc.) term.

Susan

At 3:16 PM +0530 12/18/12, Devika Ganapathy wrote:
>Also should have added - The high level search results are a list of
>technical terms listed in an accumulator. A 'search within results' function
>is required since this list could be very lengthy.
>
>
>
>From: Devika Ganapathy [mailto:[log in to unmask]]
>Sent: Tuesday, 18 December, 2012 11:26 AM
>To: [log in to unmask]
>Subject: best practices for search within results
>
>
>
>Hi everybody,
>
>I'm looking for best practices / examples on 'search within results' for a
>web application.
>
>The specific questions I am looking at are:
>1) Is it better to display two separate search boxes or use one box to
>search and then search within results?
>2) If two boxes are used, what ways can they be visually differentiated?
>3) Once a search within results is done, how does one get back to the
>original search results?
>
>
>
>Thanks in advance!
>
>Best Regards
>
>Devika Ganapathy
>
>
>
>anagramresearch
>
>Design Research + Usability Consulting and Training
>
>
>
>Skype: devika-ganapathy | Phone: +91-9886702014 
>
>www.anagramresearch.com
>
>
>
>
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