"I do not find my phone."
Translation:Ní aimsím m'fhón.
You got me curious about whether or not it was an option, so I checked in Teanglann: https://www.teanglann.ie/ga/fgb/tar_ar Interesting read!!! :-) But it looks like Ní thagaim ar m'fhón would translate to "I don't (habitually) come across my phone", which doesn't have the same sense of purpose of actively looking for something as "I don't find..."
I had wondered about the difference in these phrases too. I know 'tar ar' can be used in the sense of finding a place. That fits with the idea of 'coming across something' rather than actively looking. It's hard to learn all these nuances but it will make our Irish better.
Thank you both! That's indeed very interesting, but also very tricky. ;) I guess it's the difference between finding as in 'coming across', as you say TreasaEH, and finding as in 'locating'. I'm not a native English speaker so when I see "to find", I don't automatically think about all the different nuanced meanings of the word... especially when I also then have to translate into Irish!