Please check your SQL Query before running it in the Visual Studio.
I have used the Employees database for this Query.
DECLARE @SearchTerm VARCHAR(100)
SET @SearchTerm = '9'
SELECT FirstName, LastName, City, Country FROM Employees
WHERE LastName LIKE @SearchTerm + '%'
OR [Address] LIKE @SearchTerm + '%'
OR PostalCode LIKE @SearchTerm + '%'
Output
FirstName LastName City Country
Nancy Davolio Seattle USA
Andrew Fuller Tacoma USA
Janet Leverling Kirkland USA
Margaret Peacock Redmond USA
Laura Callahan Seattle USA