rgrep

[Hannie Dumoleyn]

As much as I would like to have this command rgrep work properly, I 
still encounter problems.
In ubuntu-docs (Precise) I found the typo "brightnest"
I tried:
~/ubuntu-docs/ubuntu-help/C$ rgrep "the brightnest colors" .
~/ubuntu-docs/ubuntu-help/C$ rgrep "the brightest colors" .
~/ubuntu-docs/ubuntu-help/C$ rgrep "brightnest" .
~/ubuntu-docs/ubuntu-help/C$ rgrep "brightest" .
I also tried spaces at the beginning and the end of the phrase. And then 
my creativity was exhausted.
Simply concluding that the typo does not exist anymore is too simple for 
me. In that case the word "brightest" should have been found.
Any more suggestions?
Hannie