For drug-sniffing dogs, generally all that is needed or expected is the dog will indicate where and when its handler wants an indication. For bomb-sniffing dogs you are hoping for a more precise outcome which is much harder to train for and achieve.
>The ADE 651 is a fake bomb detector[1] produced by the British company Advanced Tactical Security & Communications Ltd (ATSC). Its manufacturer claimed it could detect bombs, guns, ammunition, and more from kilometers away. However, it was a scam, and the device was little more than a dowsing rod. The device was sold for up to US$60,000 each, despite costing almost nothing to produce.
[1] https://www.washingtonpost.com/opinions/2019/02/05/supreme-c...