SQL Server :: Search Criteria For Multiple Columns?

im trying to write a query. for my ui ,i have 3 text boxes for firstname,flightno,sequencenumber.

i input search value on particular textbox it has to be searched on particular column of my db in a single stored procedure.

im using this procedure but it retrives only one column at atime. so like this i need to write three procedures.

but i have only one GO button.

ALTER PROCEDURE [dbo].[spp_searchUsers3]
@lastname nvarchar(50),
@Value varchar(50)
AS
DECLARE @SQL nvarchar(500)
SET @SQL = 'SELECT firstname,flightnumber,lastname,status FROM tbl_pregister WHERE '
+ @lastname + ' LIKE ''%' + @Value + '%'''