Searching on free formtext fields is tough, there is no way to control the user input...what you can do here to try and accommadate the vagaries of input
Split the input string on the spaces
Check each value to see if its numeric or alphanumeric.
If numeric, is it 4 or 2 digits long?
If 4, is greater than 1950(arbitrary year)?
If it passes all these tests then you know its the year and can plug it into the sql statement for the year search, taking only the last two digits
"...where $my_year > year_from and $my_year < year_to "
