I can help you with the first phrase. It should be 'It's like taking coal to Newcastle.'
Newcastle is a city in the North East of England where a lot of coal used to be produced.
The phrase to take coals to Newcastle means to take something unnecessary to a place where there is already a lot of this. If I took a bag of sand into the desert, or if I took some ice to the North Pole, it would be like taking coals to Newcastle.
The other phrase maybe not quite right. Are you sure you've copied it down correctly from where you found it?
The meaning is probably that if you keep working at something, even if it's a difficult problem, then after a long time you will succeed.
Hope this is useful to you.
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