1)First world problems
-Can you stop complaining about how slow your internet speed is, that is a first world problem.
-Can you stop acting like you care about the welfare of Cecil the Lion, its a first world problem, some Zimbabwean farmers are probably happy to see him gone.
-Can you stop moaning about which girl you want to ask out, its a first world problem.
Definition: a slang term used to refer to issues in First World nations that are complained about only because of the absence of more pressing concerns
Etymology: The term "First World problem" first appeared in 1979 in G.K. Payne's work Built Environment,[4] but gained recognition as an internet meme beginning in 2005.
2) Flavour of the month
-Carly Rae Jepsen became the flavor of the month after her one hit wonder "Call Me Maybe".
-Many Americans are hoping that Donald Trump is just a flavor of the month, instead of a serious Presidential candidate.
-Cecil the Lion became the flavor of the month for all the wrong reasons.
Definition: suddenly but temporarily popular
Etymology: The phrase dates back to 1930s USA and originated in the advertising slogans of ice-cream companies there. It isn't absolutely clear which company first used this in their campaigns.
3) A hole in the wall
-Ivan can eat at any hole in the wall and not get food poisoning.
-That hole in the wall has really good food.
-Calvin wanted to work hard at the hole in the wall so he could eventually work at a five star restaurant.
Definition: small dark shop or restaurant