Hello, everybody!
So, my problem. I enter "testingcheats enable", then I enter "bb.moveobjects", then "bb.showhiddenobjects" (at this point some DEBUG items appear), then "bb.showliveeditobjects". But if I compare what appears in my folder with what I see in random videos of sims 4 speed build, my DEBUG section is like 2 lines of objects, instead than 12. My problem is that only one tree appears, while I'd like to see all the bushes and the flowerbeds that I see in the speedbuild (check this Picture: for example, I have none of those items) .
Can someone explain to me what I am doing wrong? I have all the expansions, 4 game packs and 5 stuff packs, so, I mean, I should find more than 12 items!

After entering the cheats as you did correctly, you need to enter the build/buy catalog and search for the word debug,
then without hitting enter you should see a new drop down list of search results, select the **Debug** one and you should see all the items.

I've tried both
1) writing "DEBUG" in the search box
2) clicking "debug" in the select box on the upper right (the one where you can filter for color, pack, etc)
still, I see only a bunch of them T_T

Ok, I've found the solution. I will write it here, in case it can be useful for others.
After writing all the cheats correctly, I was writing "debug" in the search panel and then, just as I do for getting a full set of furniture showing, I was clicking on the highest "debug" in the search result. Instead I should have just pressed "enter" to see all the items.
Thank you all for the ideas. We can close this post, I suppose.