Tonight, I upped it to three objects. All three objects where down, including a new one, "perro" a little stuff dog. This was different in lots of areas and would present a challenge to Wally.
At first, I introduced him to "perro". I pointed to "perro" and when he touched the little stuffed dog, I clicked and rewarded him. I repeated this multiple times and then put out two other objects, his first new ball (still using "pelota") and the same bone as before, the soft, big one.
Once done, I called for "perro" again. He did go to the dog toy again, but then again, it was in the same spot and the same object he was rewarded for, so it follows that it would be his first choice. I called for "hueso" next, his bone. Now that confused him. In fact, the bone was a hard object for him to find! I don't understand why that was, but he just was at a loss to find it.
He did eventually find the bone somewhat consistently, and then I threw in "pelota". Another bit of confusion and he went back to the bone a lot. The ball was just sitting there, in plain view and he wouldn't turn around to find it. I think what happened was that his usual search pattern kicked in. Too bad for him, the ball was in the opposite direction!
Wally did get the ball, and now it was time to have him looking for an object at random. He was challenged, at times he seemed to want to give up, but I wouldn't let that happen. I don't know if I was pushing his limits, but with encouragement, my constant calling out the object, and the rewards I used (the new treats I got at the last trip to Petco) kept him going and he did find the object I called out for.
After that, I gave him a two minute break. I stroked him slowly and gently while he sat in front of me and just let him have a little time to recover and unwind.
Then I tried to add 'dónde está?' so I would say 'dónde está perro?', for example, and he had to at least go to the proper object, the dog toy in this case. Once I did this, he got the object a couple times and brought it to me, but I think it was too much. Also 'dónde está?' is the "find it" cue so that might have entered his mind. A positive (at least in my view it's positive!) sign is that when I said 'dónde está?', he was ready to look, but waited for me to stay the object name. He may have been waiting for the object name to know what to go looking for - something for me to watch going forward.
I switched to "go get _____ " and that helped him. For now, I think I'll stick with that, at least for these exercises.
We had been working for about 30 minutes, so I ended the session, let him jump up on me and let him unwind and process things (he's currently sleeping next to me).