It doesn't matter what is being searched for or in what module the search is being performed in/from. The crash is always immediate. The net result is that one must manually browse possible help areas looking for a term that could be searched globally in an instant if the SEARCH feature was working as it should.
On pc Debian x86-64 with 3.6 branch updated yesterday, I don't reproduce this problem. On what env are you? What language do you use? Did you install any specific extension? Did you try after having renamed LO directory profile? (see http://wiki.documentfoundation.org/UserProfile)
Thank you, Julien. The Problem Was A Very Old User Profile. When I renamed "user" to "user-old", and restarted libreoffice as instructed, the problem went away, and I am able to search the Help documentation correctly.
So it must be related to fdo#43489 (see https://bugs.freedesktop.org/show_bug.cgi?id=43489) Could you attach your buggy LO profile directory zipped?
*** This bug has been marked as a duplicate of bug 53337 ***