Some quick find examples

find in current directory all files that have size greater than 0

• find . -type f -size +1 -exec ls -la {} \;

find in current directory all files that have size less than or equal to 0

• find . -type f -size -1 -exec ls -la {} \;

find in current directory all files that have size less than or equal to 0, then remove them

• find . -type f -size -1 -exec rm {} \;

find a file that is exactly 5 days old

• find . -type f  -mtime 5 -ls
• find . -type f  -mtime 5 -exec ls -la {} \;

find a file that is 4 to 9 days old

• find . -type f  -mtime +3 -mtime -10  -ls

find  a file that is exactly 5 days old, then remove it

• find . -type f  -mtime 5 -ls
• find . -type f  -mtime 5 -exec rm {} \;

find by different types.  This is not a complete list:

• find . -type f -print
• find . -type l -print