I need to repurchase apps for free but I can't

Hi, I have a MacBook Air bought last year in August, I had some problems with it so I brought it to a Best Buy to fix it, and they did it but had to downgrade it to the version 10.9 (OS X Mavericks). Everything seems to be good except that when I got it back they deleted all the datas, naturally I have a backup, even if not made with Time Machine, with all my files, but I didn't move some apps from my computer to the hard disk cause I tought that they would have been memorized in my Apple ID in iCloud and I could have repurchased them for free; but those apps are not saved on my account and besides apps like iPhoto, iMovie and Garage Band are not on my computer, even if I got those when I bought my MacBook.

I don't know if there is something wrong with my computer or my Apple ID, but I can't get my old apps for free, can you help me?