Thats kind of cool, scraping Iota off twitter. I just happned to recently be intrisetd in Iota.
I have two ideas that you might like. One is use a case sensitive search. The results above have a few non crypto tweets, they are all using iota not Iota. so only pulling in Iota with a capital I will narrow down to mostly crypto related tweets.
The second is to find a way to pull the whole tweet, there were some I was interested in but only could read up to the ... part.
Good Luck!