I feel like my working memory is 80% of what It needs to be. For concepts to click, 5-ish concepts have to be kept in actual awareness, so that you can see all their relations, and for the conept to click. My head is often 20% too small for me to be able to do this. Is there any way to improve this?

Memory techniques don't work, as they're usually very domain-specific. Memory palace, etc. The only thing that seems to work is making sure your general health is up to standard, but I already exercise, eat healthy, get a lot of sleep etc. Is there a drug I can take, an exercise I can do, some habit I can pick up that will help? Please post actual studies.