Question

Does anyone know how to get the tm poison jab in oras?

Answer 1

The Poison Jab TM is on a Mirage Mountain in the northern part of the map (out in the ocean). Each day a new Mirage spot spawns, so you can change your 3DS clock to keep resetting until it appears. You'll need the Acro Bike to reach the TM's exact location.

This page has a step-by-step tutorial on getting the TM.

I'll also add a screenshot below of the exact mirage mountain to look for on the map. The source of this screenshot is from the tutorial linked above:

Answer 2

In ORAS the TM, TM84: Posion Jab is found in Mirage Mountain (North from Lilycove City (Requires Acro Bike))

Source: http://bulbapedia.bulbagarden.net/wiki/TM84