How To Randomly Choose Zero Strings From A Line

I have been working off of this question: How To Randomly Choose Strings From Same Line In File and we are able to randomly select 1-2 strings. But, I'm stuck trying to return 0-2 strings.

Here's the code I'm working with:

while read -r line; do
    elements=(`echo "$line" | grep -oP '(#\S+)' | shuf`)
    show="${elements[$((RANDOM % ${#elements[@]}))]}"
    if (((RANDOM % 2) == 0)); then
        elements=(`echo ${elements[@]//$show}`)
        show+=" ${elements[$((RANDOM % ${#elements[@]}))]}"
    fi
    echo "$show"
done < file1.txt

My attempt:

cat file1.txt | while read -r line; 
do elements=(`echo "$line" | grep -oP '(#\S+)' | shuf`); 
show="${elements[$((RANDOM % ${#elements[@]}))]}"; 
if (((RANDOM % 2) != 0)); 
then show+=" ${elements[$((RANDOM % ${#elements[@]}))]}"; 
fi; 
echo "$show"; 
done | awk '{ while(++i<=NF) printf (!a[$i]++) ? $i FS : ""; i=split("",a); print ""}'

Here's file1.txt:

#Sample #Example #StackOverflow #Question
#Easy #Simple #Code #Examples #Help
#Support #Really #Helps #Everyone #Learn

It would randomly output:

#Question
#Code #Examples
#Helps

Let's say, I want to have no strings returned randomly:

#Simple #Examples
#Everyone

I know it has to do with the logic of if there are 0, but can't get it to return 0 results. If you guys can point me in the right direction. I would appreciate the input and support of the question.