Hello,
I've finally find the solution:
xdXDocument:GetDOM("Data from SharePoint")/dfs:myFields/dfs:dataFields/dfs:CheckList/@Required[../@Cavitation = xdXDocument:get-DOM()/my:myFields/my:Cavitation and ../@Customer = xdXDocument:get-DOM()/my:myFields/my:Customer and ../@Project_Type = xdXDocument:get-DOM()/my:myFields/my:ProjectType]
where I have the column Cavitation, Customer and ProjectType as column in Sharepoint.