The on-loan Getafe hitman has yet to score a goal for the Hoops since arriving in August.
He admitted he was frustrated last week with his time at Celtic after being used as a bit-part player, but failed to impress after being handed a rare start against Kilmarnock last week.
And the Venezuelan ace admitted the SPL is a learning experience for him.
He said: "It's hard to adapt to life in Glasgow and the football played in Scotland. What was clearly a yellow card in Spain is not in Scotland.
"For example, last week the referee told me I had to change my shirt because it had blood on it.
"And I said to him. 'Yes, it is my blood because I got fouled and you did not whistle for it.'
"But despite my difficulties, I hope this slump ends soon and return to being the player I've always been."
Miku was also dropped from his national team for this month's friendly with Nigeria because manager Cesar Farias was unhappy at his lack of playing time at Parkhead so far.