9.2.4.3.1 Supported Constructs:

Supported Constructs	Description
/e	Use the absolute path from the root of the document to match e.
./e or e	Use the relative path from current node being processed to match e.
../e	Use a path based on the parent of the current node (can be repeated) to match e.
//e	Match e wherever it occurs in a document.
*	Match any element. Note: Partially wild-carded names are not supported.
[n]	Match the nth occurrence of an expression.
[x=v]	Match when x is equal to some value v where x can be: @att - some attribute value text() - some text value name() - some name value position() - the element position