I'm having problem using cc of research_all_technologies and research_technology or technologies can't remember. But when I use research_all_technologies only non repeatable researched but not repeatable ones and research_technology/technologies it says it needs augment something so I don't understand whats it saying.
From the wiki:
research_all_technologies :Instantly researches all non-repeatable technologies as of 2.0.2 update. Previously, this was research_technologies. Add 1 for creature and crisis techs too. Add a second number for repeatable technologies. Example: research_all_technologies 1 4
research_technology : Instantly research one technology. Takes technology key as argument. Example: research_technology tech_titans
So yes, in first case the argument is optional (unless you want to research also crisis and repeatable technologies), in the second case you need to provide the name of the technology you want to research.