The process of thought collecting

When I leave my home I always try to bring a notebook and a fountain pen (or two) with me. I've had my midori travel's journal for work appointments and day to day planning, a little notebook here and there for when a random inspiration hits me and need to write it down, I have a notebook at my PC at home for making notes during podcasts I listen to, a gratitude journal and a quote journal... on a random day, this would be what my desk looks like, a multitude of notebooks on my desk going on at once. The looks of it can be quite over-whelming to the outsider, but I have my own system I am working with and suited me fine. But then I wanted to look up something I knew I had written down somewhere, but I couldn't find it. All these loose journals were serving me well as brain dumps, but it wasn't providing the structure I needed when I wanted to follow up on things. I was looking into Bullet Journaling some years ago but decided that that was a "difficult structure ...