Cells become unorganised after using Search Bar

I am using Search Bar and Search Display programmatically, the search and results are all working fine. The problem is with the cell hight when display the results, the cells shrink and become smaller as shown in the image;

Her is the code I am using to control the cells hight:

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{

if (self.listArray.count >= 1) { //change 0 to whatever cell index you want taller
return 159;
}
else {
return self.listArray.count;
}

}

How can I control the cells hight after display the results?

Thanks