I am still having trouble understanding what you are trying to do, your english is not so good. I will try and help you anyway.
Do you want to search or sort? You are saying that you want to search but in this situation people normally want to sort. If you want to search then obviously you must have a fill-in to enter the value to search for, why not just use this with either a combo or a radio-set next to it, it visually makes more sense to the user to activate the search this way.
However if you are wanting to SORT by the column clicked then use the START-SEARCH event of the browse this is triggered when you click the column-label.
If you still need help then feel free to ask.