see the forest for the trees

To see the forest for the trees suggests that a person is capable of discerning the bigger picture, from observing the more granular details. Conversely, when used in the negative form, this suggests that someone is easily preoccupied by the details, thus allowing them to obscure the bigger picture.

It means that if you look at things one at a time, you might not realize that a branch of separate "trees" go togehter to make a "forest"

When you are too close to a situation you need to step back and get a little perspective. When you do you will notice there was a whole forest you couldn't see before because you were too close, and focusing on the trees.
Simply that you have focused on the many details and have failed to see the overall view, impression or key point.

To be so concerned with specifics or details that the larger problem, situation or point is missed. Alternate: can't see the woods for the trees. Often said incorrectly as "can't see the forest THROUGH the trees." (English, circa 1500's)

To become so caught up in the small details that you're unable to step back see what is going on or what will happen. Our take of reality gets bent as we are too involved.

Like when person is so focused on finding an error in day a book, that they didn't take the time to enjoy it for what it was; a story.

Another would be say a brother or siser begs you to hide them, acts nervous (you ignore this) They look out windows (you ignore this too) as you just want to catch up. They ask you to hide a knife .... a bloody knife ..

The trees fall away yet?

When a person focuses too much on small detail (trees), and misses the big picture (forest).

This term means someone is so simple minded that they can't figure out the simplest problems. Their minds are like great big empty voids of any kind of logical thought. This is why even though the can see the trees their simple minds can't grasp that's the forest.