Is this what you want? It seems kind of strange that you’d have these complex tunnels hidden in the cube…Ant condos?
In my experience, for mesh booleans to work, the edge lengths all have to be somewhat similar, and the cube and pores had much longer edges than the tubes, so I tried to put them nearly in the same scale. For my own curiosity, I split the result down the middle and opened the cube up to see what was happening inside.