Attribute Unsupported error on some apps while finding element

[Pramanth]

Getting below error while searching for an element which do not exist on few of the application like MS Office word 2011. In other application returns nil when element is not found.

What may be the cause and any pointers for solution?

w = AX::Application.new 'com.microsoft.Word'
w.search(:static_text, value:'Save A:')
ArgumentError: attribute unsupported
from /Library/Ruby/Gems/2.0.0/gems/AXElements-7.0.1/lib/ax/element.rb:77:in children' from /Library/Ruby/Gems/2.0.0/gems/AXElements-7.0.1/lib/ax/element.rb:77:in children'
from /Library/Ruby/Gems/2.0.0/gems/AXElements-7.0.1/lib/accessibility/enumerators.rb:24:in each' from /Library/Ruby/Gems/2.0.0/gems/AXElements-7.0.1/lib/accessibility/enumerators.rb:43:in find'
from /Library/Ruby/Gems/2.0.0/gems/AXElements-7.0.1/lib/ax/element.rb:271:in search' from (irb):95 from /usr/bin/irb:12:in