I am the only one who dont understand why the most popular sell on my portfolio is not really my most popular of all time. Is more like the most popular sell for the last week or something like that. 

From what I can tell "Most popular" has a weighting so that newer views and buys are weighted higher. My new images are always my most popular for a short while before they usually sink into obscurity.

Pauws99 has it right -- there is a time weighting of any decent search.

Think about it.  If that were not the case, your search would give you results that were 20 years old, because they were popular at one time and that popularity kept them at the top... which means they stay popular.

The only way to get more current information is to include a time weighting.

my "Most popular" was #1 for years and still is My Most popular By sales and now on page 89 in that category.it went there in One Minute about 5 years ago. "New" is about the Only thing thats correct at SS.