XPath working on Razor but not on Multinode Picker

Questions
1

My xpath query does not work when used with multimode picker but works when used like Umbraco.GetContentAtXPath in Razor. It also works if I execute the query on a visualizer tool like XPathPizualizerTool

Below is the query and the content.

Query:

//TeamMembers[TeamMember[categoriesMainSite[contains(text(),"Blog Authors")]]]

Content:

<TeamMembers id="..." key="..." parentID="..." level="2" creatorID="0" sortOrder="7" createDate="2016-02-15T16:36:20" updateDate="2016-02-15T16:36:20" nodeName="Team Members" urlName="team-members" path="-1,1239,1325" isDoc="" nodeType="1175" creatorName="Virca" writerName="Virca" writerID="0" template="1174" nodeTypeAlias="TeamMembers">
      <showSponsors>0</showSponsors>
      <TeamMember id="1330" key="e1d7bd14-6aa7-4a44-ac01-27e20b6315a7" parentID="1325" level="3" creatorID="0" sortOrder="0" createDate="2016-02-16T08:42:08" updateDate="2016-02-16T08:42:08" nodeName="Lazau Florin-Ionel" urlName="lazau-florin-ionel" path="-1,1239,1325,1330" isDoc="" nodeType="1173" creatorName="Emanuel Virca" writerName="Emanuel Virca" writerID="0" template="1172" nodeTypeAlias="TeamMember">
        <firstName><![CDATA[Florin-Ionel]]></firstName>
        <lastName><![CDATA[Lazau]]></lastName>
        <categoriesMainSite><![CDATA[Blog Authors]]></categoriesMainSite>
      </TeamMember>
      <TeamMember id="1331" key="4c385076-5025-44e0-8440-35be66306184" parentID="1325" level="3" creatorID="0" sortOrder="1" createDate="2016-02-16T08:42:36" updateDate="2016-02-16T08:42:36" nodeName="Virca Emanuel" urlName="virca-emanuel" path="-1,1239,1325,1331" isDoc="" nodeType="1173" creatorName="Emanuel Virca" writerName="Emanuel Virca" writerID="0" template="1172" nodeTypeAlias="TeamMember">
        <firstName><![CDATA[Virca]]></firstName>
        <lastName><![CDATA[Emanuel]]></lastName>
        <categoriesMainSite><![CDATA[National Advisory Board,Staff,Board of Directors,Chapter Board Members,Leadership Council,Trainers]]></categoriesMainSite>
      </TeamMember>
    </TeamMembers>

The query does not take into consideration the contains function of the query and always returns all the members.

Any Help Please?

This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/75108-xpath-working-on-razor-but-not-on-multinode-picker