There won't be anything that will be logged showing what work was done by the tech that worked on your computer. The logs only record information about what the system is doing or error conditions.
If hardware you won't see much. Or if something in bash best you'd find is them calling up text editor of some kind. Me I like nano...but that's me. Nothing in bash history would be detailed from this, all the changes in the config file(s) looked at would not be seen. This is why when I work on Linux systems I take good notes on what I am doing. All I see in my bash history is sudo nano somefilename usually followed by that services restart command.....whatever I did in that file not recorded.
EDIT: there are methods for these changes but that be a real geeky tangent of commenting in files, content versioning systems....bit outside this thread probably
If software besides bash history mentioned something might be in in your individual app logs, if they even have them.
Even in windows not all application tie into the central logging system besides application log (which most times are vague and has you really need to go to the actual application logs files anyway).
Where your app logs would be you'd have to research from them. What would be in those logs can vary as well.