Affiliate Marketing Secrets

Hi there,
I have a niche website at http://www.3holepuncher.org
basically what it does is that it allows 3 holes to be created.
I realised that searching this term “stapleless stapler” gives me a high rank at the serp -11
compared to 3 hole puncher without quotes at rank 19.
There is also variants of the keyword 3 hole punch,3 hole paper and 3 hole paper punch but all of them rank much lower.
Basically,when I went to google keyword analytics.The keyword global monthly search is the same for all the variants.
Should I modify my website to include all the variants of the keyword,it should be able to bring up the search engine ranking higher?