You know the closer you get to something是什么意思？

You know the closer you get to something
The tougher it is to see it
And l'll never take it for granted
这是在一个歌曲里看到的，请问这段话是什么意思？小弟在此谢谢了~
不好意思我是想说对这段话的每一句进行翻译。我想了解这个歌的每句话~

If you know the ... Do you know the professor do you know the man ( )? [ ]you all know the news. You know Sex and the City? Do you know the boy ----by Tom? do you know the meaning of echo what do you know about the sea? The oldest person you know is-------------------------- what's the--------do you know?