Impossible to access to my keywords (more than 300)

Using research function, as I have more than 300 keywords I can't acces to the first one begining from A.... to G.....
It's impossible to scroll
Does somebody encouter this problem or is it jus an Iphoto limitation?


Ah yes. There that is a problem.  You might look into using a DAM (digital asset management) application that can handle and search by keywords a bit easier.   I use Media Pro 1. 
If you follow the directions in the tutorial below you can create an MP1 catalog of your iPhoto library original photos complete with keywords.  Then test the search by keyword by clicking on one or more of the keywords in the left hand pane under organize.  You can even setup hierarchical keywords. 
MP1 lets you manage the folders, rename files, write meta dagta to the files and lots more. MP1 is available as a 30 day demo.  It doesn't not affect your library as long as you only use it to view files and not edit, move or rename them.