Pronounciation

I sometimes have abit of difficulty in saying some particular words.
For example,

1) I once wanted to say to go to LIBRARY, but instead I said I want to go to STRAWBERRY

2) I was watching Harry Potter and popo kept telling me the name of the movie but I could only say it as " Helicopter"

I was abit shy when seeing mum and popo laughed at me. But now I have these two particular words pronouced perfectly correct. Popo sometimes kinda tricky and tried to confuse me and lead me to say it wrong but I learnt the lesson and I know which one is correct.