I'm not sure if I know really what I'm doing on the idle stuff, but it's been fun messing with it. Sometimes I seem to get them often, and other games I'm not, and not sure what I'm doing to initiate those to come through.

Go to the tech tab (third from the right). Behold the tech tree. Click/tap on a tech that you do not already have. Behold the resource requirements (alloys like copper bars and/or items like screws). Accumulate those resources using smelters, crafters, resource caches, or markets. Go back to the tech and click/tap the "Unlock" button. Now you have the tech.