Você já tentou algo assim:
SELECT ColumnName
FROM TableName
WHERE ','+ColumnName+',' LIKE '%,searchword,%'
Ou:
SELECT ColumnName
FROM TableName
WHERE
ColumnName LIKE '%,' + @searchword + ',%'
OR ColumnName LIKE @searchword + ',%'
OR ColumnName LIKE '%,' + @searchword
OR ColumnName = @searchword
Espero que isso ajude