It may be difficult to find the "perfect" strain, but what many new users miss is that most strains are actually very similar in how the cannibinoids affects your wellness. The mental feelings may differ drastically and there is a significant different between sativa and indica, but past that things start to smooth out for many illnesses. This is because many of them are mostly helped by either THC or CBD.
Currently there is not a lot of research on specific strains, just a lot of evidence that cannabinoids can help your lungs to open up. Since cannabis has such a low risk for patients, I would recommend vaporizing a hybrid cannabis strain. Try asking your budtender for a nice middle of the road strain that does not have the properties to cause you anxiety (just in case you are prone to those types of feelings)