I solved myself for the first part. Ye~~~. I need to put where clause in Query object so it can query specific field without adding another map service or changing display name field.
I'll be glad if someone knows how to fire up the query right after selecting an item from combo box.
Thanks,
<esri:Query id="queryteam" text="{cbxTeam.text}" where="EOC_STATUS = '{cbxTeam.text}'" returnGeometry="true" outSpatialReference="{mainMap.spatialReference}">
<esri:outFields>
<mx:String>EMPNO</mx:String>
<mx:String>FNAME</mx:String>
<mx:String>LNAME</mx:String>
<mx:String>ADDRESS1</mx:String>
<mx:String>CITY</mx:String>
<mx:String>EOC_STATUS</mx:String>
<mx:String>POSITIONTITLE</mx:String>
<mx:String>TITLE</mx:String>
<mx:String>HMPHONE</mx:String>
</esri:outFields>
</esri:Query>
++++++++++++++++++
<mx:ComboBox id="cbxTeam" prompt="select a team" selectedIndex="-1" dropdownWidth="150" horizontalCenter="0" top="20" >
<mx:dataProvider>
<mx:Array>
<mx:String>A</mx:String>
<mx:String>B</mx:String>
<mx:String>C</mx:String>
<mx:String>D</mx:String>
<mx:String>Not Assigned</mx:String>
<mx:String>Not Avail</mx:String>
<mx:String>Not Avail-B</mx:String>
<mx:String>Not Avail-D</mx:String>
</mx:Array>
</mx:dataProvider>
</mx:ComboBox>