Finding the right file seems like a simple task, but for example, if you are a bookworm like me, and you have thousands of books on drive, then you might rethink the situation.

while file managers can sort things according to size, they lack filtering and the convenience of customization.

the Terminal comes to the rescue! with the “find” tool.

here is an example of using it :
  
$ find ./ -type f -size +500k -1000k -exec ls {} \;

now let’s explain :

find : the tool that searches the directory for the files.
./ : the directory being searched, in this case, it's the current directory.
-type f : the type of the item being searched fore, in this case it's a file!
-size +500k -1000k : the size range, more than 500k and less than 1000k.
-exec : executes an auxiliary program.
ls : the auxiliary program being executed. in this case it's the "ls" tool which lists files in a directory.
{} : this is the file listed by "ls", passed along by "find".
\; : ends the exec.