I'll repeat my tired, old advice about supplements - look for independent evidence that the products you are about to take are:
1) Safe, 2) Have demonstrated effectiveness & 3) Are pure & of the advertised potency. Curious about Dr Tobias Lung Cleanser, I looked up the individual ingredients to see whether these are known to help lungs, and what drugs each might interact with.
Vitamin C 125 mg (fairly low dose) available everywhere
Menaquinone - this is Vitamin K2 - is it deceptive to list like this? Most people get plenty from their diet.
Butterbur - MAY help allergic rhinitis. Interacts with Rifampin (1 of the Big 3)
Quercetin - MAY be anti-inflammatory, no mention of lungs. Interacts with antibiotics and blood thinners.
Bromelian - Enzyme, slows clotting, may cause allergic reaction if other plant/pollen allergies. No mention of lungs. Interacts with antibiotics and blood thinners.
Citrus Bioflavonoids - Help body process Vitamin C. No mention of lungs, no stated interactions.
Feverfew - MAY help migraine, lungs not listed, slows clotting, may cause allergic reaction if other plant/pollen allergies. Interacts with blood thinners and drugs metabolized by the liver.
Stinging Nettle - May help with osteoarthritis, may lower blood sugar. No mention of lungs. Interacts with diuretics, lithium, blood thinners and anti-diabetes meds.
Pine Bark - May help asthma, knee osteoarthritis. Increases immune reaction. Interacts with blood thinners, immunosuppressants and anti-diabetes meds.
Cordyceps - May shrink some tumors. Stimulates immunes system. Interacts with blood thinners and immunosuppressants.

Whew! That little exercise took me about an hour. What I learned was there are a number of vitamins, herbs and enzymes in this supplement, but none is especially recognized as helpful for "cleansing" lungs. And that many of the ingredients could potentially interact with prescription medications, some of which I have taken.

What to do to cleanse your own lungs safely? Use lung medications, or or inhaled, as prescribed. Use saline nebs to loosen mucus followed by rigorous airway clearance. Drink plenty of water and eat a healthy, varied diet to get the nutrients you need. Exercise to maintain or improve lung efficiency and keep secretions moving.

Sue