For some blogs and websites, even keywords with 0 monthly searches may be relevant.
My other blog – blackbeltwhitehat.com has built all of its traffic off KWs that Google KW planner says has 0 searches.
It all depends on how authoritative your website is and your competitors are. You can go after bigger, more popular KWs if you are a huge website with a DA of 90. It’s a different ball game if you are running a personal blog with a DA of 15
Try and include a number of the relevant searches in your articles etc.