trying to move hierarchical keywords up and down in the thesaurus

[jma]

I am doing a bit of housecleaning and reorganizing in my database and am trying to determine how I can most effectively move hierarchical thesaurus keywords up and down in my keyword hierarchy. 

I see that there are two icons/buttons (circled in red in the attachment) which would apparently provide this functionality, but I have yet to figure out how to make them active.  Any suggestions?

Thanks,
--John

[Mario]

See Editing Thesaurus Elements