Is there a length limitation for a long tail keyword?

Is there a length limitation for a long tail keyword?I choose a long tail keyword" Adidas Water Grip Surfing Shoes ".But I can never find "Adidas Water Grip Surfing Shoes" on Google Webmaster Tool.Instead,I only find "Adidas Water Grip","Adidas Water Grip Shoes","Water Grip Adidas","Adidas Water","Adidas Watergrip","Adidas Water Shoes" and "Shoes in Water" on Google Webmaster Tool.It seems that there is a length limitation for a long tail keyword.However,I can also find "mac studio fix powder plus foundation" on Google Webmaster Tool,which is longer than "Adidas Water Grip Surfing Shoes".I am confused.Please help me out with it.

 

Mostly all use 3 word phrase for long tail keywords ...how much you want to expand your keyword like that your keyword searches also decrease so avoid more than 3 words..if your keyword is " Adidas Water Grip Surfing Shoes " means try to use your keyword like "water-grip-shoes" "Adidas-watergrip-shoes" etc.

And google crawl first 60 char only in meta title so if you keyword like " Adidas Water Grip Surfing Shoes " you cant able to add another keyword in that place (meta title) so avoid long tail keywords.

 

if you can not find it on Google Keyword Tool, meaning that nobody searches for that keyword

 

No, there might not be a limitation but you would not want to increase it more than 4 words. You would get highly less searches and it would probably not worth the effort anyway. 3 word keywords are usually acceptable and are more than often used.