Well,let me try this time.
1 sugar coat, means,when you tell someone something not so good,you won't tell him directly or maybe no the truth,i.g.:Don't sugar coat the truth and just tell me what happened exactly!
you should also use "sugar coated" as an adjective.
2 It seems to be like trying to find a flea on an elephant's ass.
it has the same meaning with "look for a needle in a bottle of hay",means something impossible.
i.g:Finding you in crowd seems to find a flea on an elephant's ass,it is impossibe.
Keep on studying and have fun everyday!