Here is an example of using the SearchConditionList with a variable parameter.
<SearchConditions
xmlns="http://www.teradp.com/schemas/GN4/1/SearchConditions.xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
ObjectTypeName="folderObject">
<SearchNode xsi:type="SearchConditionList">
<List xsi:type="SearchCondition"
Path="[folderObject.folderRef.path]" Op="Equal">
<From xsi:type="VariableSearchNode"
Name="folderPath" Type="String"/>
</List>
</SearchNode>
</SearchConditions>
This xml code defines a search for folderObjects (ObjectTypeName="folderObject") which reference a single specific folder, defined by it's path. It uses a parameter named "folderPath" (Name="folderPath") to pass the path of the folder, as a string (Type="String"), in which to search.
It returns a list of folder objects which have a folder reference (Path="[folderObject.folderRef.path]") equal to the parameter which is passed with the call.