Ah, pet peeve time again:
When they can't articulate just what in the fuck they want.  They ask where they can find [that thing] but don't explain what it is, what it does, don't have a name for it, and basically just waste my time.
Case in point:
Them: do you have one of those copper things that help with knee pain?
Me:  I'm not sure, is it like socks?
Them:  no, it's got copper in it.
Me:  is it ointment?
Them:  no, it's like those things you put on your arm to stop swelling.
Me:  is it a compression bandage?
Them:  yeah, that's it.
Me:  *searches mydevice/zebra thingie using 700 search terms and comes up with zilch*
Me: I'm not finding any compression bandages with copper in them.
Them:  Well it's like those things that you wear around your neck.
Me: [getting angry now]  Uh, what?
Them:  You put it around your neck and it keeps your arm still.
Me: OH A SLING???
Me: *already typing "sling" into search field*
Them: YES!!!
Me:  nope, we don't sell slings but [insert name of local surgical supply company] carries them and your doctor can write a prescription for it.
Them:  that's not what I want, it has copper in it.
Me:  well, if it's not a compression bandage and it's not ointment and it's not a sling, then is it a bracelet type thing?
Them:  IT'S NOT FOR MY WRIST, IT'S FOR MY KNEE.
Me:  uh, is it compression socks?
Me:  *silently wishes for death*
Them:  yeah, compression socks, that's it.
Me:  *sends them to correct aisle*
I'm not kidding, this happened this week.  I wanted to die.