Looking on the internet deeply has found these results:

fishburger is the most popular phrase on the web.

fish hamburger 112,400 results on the web	fishburger 1109,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
You ate fish at Hamburger Heaven.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

fish hamburger

112,400 results on the web

fishburger

1109,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.