Your nodes are not indexed therefore not searchable.
Please index your nodes before attempting to search for them – as
other users have suggested, you need to make sure that the Node
actually exists before it is indexed.
You can force an index rebuild with knife: ‘knife index rebuild’
Have you considered using Chef Solo to learn, Hosted Chef  to proof
of concept data-bags, search and environments (and then, once you are
familiar…) Chef Server internally? In the order I’ve suggested, you
would gain an understanding of the core framework, the server-side
components (from a client side API perspective) and then of course
hopefully (or not!) be able to operate the server side components
(FOSS versions) yourself.
Opscode offers public training, private training and all of the course
material (CC licensed) too – may be relevant to your interests. 
I’m also aware of a number of development operations / systems
engineering consultancy organizations who may or may not be willing to
assist you – many of them whom frequent this list.
On 24 June 2012 10:46, Jorge Espada firstname.lastname@example.org wrote:
if you have nodes registered on your chef server, something like: knife
search node ‘name:*’ must return something
On Sat, Jun 23, 2012 at 10:25 AM, Brian Akins email@example.com wrote:
On Fri, Jun 22, 2012 at 8:11 AM, meenakshi agrawal firstname.lastname@example.org
knife search node ‘name:idm’
Does ‘knife node show idm’ return the expected results?