Most search engines have an option to restrict searches by using words like
"not", "and", etc. You might try adding "not" and the address of the archive
to your search. This should eliminate the references from the archive
address. So to search for gum bichromate try something like:
gum AND bichromate NOT alt-photo-process
This method *should* find only references for gum bichromate (where both
words are present in the text, without calling up "Wrigley gum" or
"bichromate disposal") but excluding those from the "alt-photo-process"
address. Some search engines use the symbols "+" or "-" for the same
purpose.
It doesn't always work as expected, but usually narrows the search results
quite a bit. As an example, I once did a search for >"Van Dyke Brown" AND
"alternative process" AND "photograph"< only to get web references to many
people named Brown who were living alternative lifestyles and processing past
incidents in their lives. Usually they included a photograph on the webpage.
Joe