There is no direct flight from Pokhara to Tumlingtar.
But the only possible way is by considering connecting flight to Kathmandu. Which means you have to take the flight from Pokhara to Kathmandu and then Kathmandu to Tumlingtar.
There is still another chance, which may not practical for all. You can charter plane. This can be consider as the good one if you have enough group member in your team.
In this process you will book 2 different ticket/sector independently.
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