When Searching for a Second Product

Your current query will produce

WHERE 'company_products.sys_id' = $product_1
AND 'company_products.sys_id' = $product_2

The second where should be an or_where so it will produce

WHERE 'company_products.sys_id' = $product_1
OR 'company_products.sys_id' = $product_2

PHP Code:

$this->db->where('company_products.sys_id', $product_1);
$this->db->or_where('company_products.sys_id', $product_2);