It was possible to restrict search in Google Scholar by subject area, e.g. it was possible to select Engineering, Computer Science, and Mathematics in Advanced Scholar Search, which had the same effect as including as_subj=eng in the url, e.g. like this.
I was able to find the old Advanced Search interface in Google cache:
Here is a larger screenshot from the same cached version.
However, now I am only able to get to Advanced Scholar Search which looks like this:
So my questions are:
- Is it possible to find the option to select subject areas?
- Does adding
as_subj=enghas the same effect as before?
EDIT:
As I learned here, you can still get to the old interface like this: http://scholar.google.com/schhp?sciui=2&hl=en&as_sdt=0,5.
However I do not know whether they plan to get rid of the old interface eventually. I also tried a few searches and it seems that results are different: Example: old interface vs. new interface.
Anyway, I still would be glad if someone could add official information from Google.
EDIT 2 (2013/03/15): Perhaps I should add that now there is no difference between the behavior of the two links above, so I do not know about any way to access the old interface anymore.
Best Answer
It had been gone in redesign few months before you asked this question and most probably you had enough time to assure yourself it won't return ever.
One mitigation would be adding those keywords from topic to search query text. The other could be limiting search down to particular publishing site with site:example.com/path stem, if you know that info in advance.