While interviewing a QA candidate, we showed him our company's game from the Google Play Store.
We asked him to play a bit and tell what the game is about. The game is simple enough, and we expect him to quickly understand when the game is over, what each item gives the player, etc. This is a test to see his logical thinking.
After that, we told him to test the game at home and find critical bugs, such as crashes, game freezes, wrong game-play and other situations that can frustrate the player.
This is the second candidate that sends results for about 6-9 issues found. The issues are mostly UI specific, such as when you press 2 buttons simultaneously or 2 buttons in a sequence in the menu, or when you turn the internet on and off and then press "Show an ad". Nothing related to the core gameplay, and nothing really critical.
At this point we are unsure whether the candidates aren't good enough or we aren't good enough interviewers to give the right task. We are developers and we have just started trying to hire a QA for our team. Should we fully describe the game and only then ask to find bugs? Or should we do anything else?