When I see the jeep coming my way...
Move off to the driver's side, crouch, and keep my *empty* hands visible.
Yell toward the jeep (english):
Hope you've got a medkit, guys. We've got two men down with multiple hits. I'm no medic, but the fellow I'm with seems to know a bit about first aid and he's calling for a medkit.
Wait for them near pulling alongside, then make one hand into a fist, thumb up, and wiggle it... hitchkiker style....
I could use a lift back to the wounded. Those buggers were drag-arsing us along behind the jeep like a line of slave labourers in some bad old B movie....
I study the newcomers, trying to ascertain details of their uniforms, apparent ranks (if any), and any trade identifiers I can see. Also, do my best to appear utterly non-threatening.