Often as soon as you start working outside it becomes harder. So many distractions. They key is just repetition, practice, and doing just as you did earlier and knowing when to call it quits. If she is eating grass and just not ‘into’ the game, better to come back later and try again.
Quick note. Try to remember, and this is a hard one to internalize for all of us, just give the “truffle” cue once unless her focus is broken. If you watch she goes into working mode right away. You want to give her the chance to work without saying the cue again as it will eventually lose its meaning if overused. There was one point when you removed something from her mouth and then asked her to work again- that is a situation where it is good to repeat the cue as you are attempting to get her to focus.
Another thing to keep in mind when starting outdoor hides: It is great you are having someone else hide the truffles. Also try to touch other things, plants, trees, walk around a bit before and after placing the truffle. I don’t believe Fancy does this, but you want to make sure she isn’t just following your scent to the source of the truffle.
Also Fancy is doing an amazing job with all those distractions! At one point she sees the other dog, breaks concentration and then after about 1.5 seconds, goes back to the game. Excellent teamwork. Good Work. And it looks like a lovely park and great place to do hides provided she continues to handle that level of distraction going on around her! Good work.
It also looks like, on that second hide, that she found it, moved off, and then when you asked her again, she went back to it (Which is great!). It takes practice, but ideally until the two of you are really in-sync try to know where the truffle is hidden so you can be spot on with timing when she finds it. You don’t want her to leave the source of the truffle once she has found it if possible.
She also was doing a great job of dropping the tin