php - MySQL UNION returning no results whatsoever -

i've been tearing hair out @ inability understand seems simple issue. i'm making small business contacts system enable our company store contact details of other business/companies business contacts (can freelancers or linked added companies. i'm trying have 1 search form enable me search either name of contact or name of business in both arabic , english. what doing wrong?

update: union query works if remove arabic search portions each query section (i.e. removed "or contact_name_arabic '%".$querystring."%'" "or company_name_arabic '%".$querystring."%'")

this becoming more complicated :/

table 1: companies

id   |   company_name   |   company_name_arabic ----------------------------------------------- 1    |   red arrow      |   السهم الأحمر 2    |   white tower    |   البرج الأبيض 3    |   mobilex        |   موبيليكس 

table 2: contacts

id   |   company_id   |   contact_name   |   contact_name_arabic ---------------------------------------------------------------- 1    |       1        |   saeed adam     |   سعيد آدم 2    |       1        |   andrew white   |   أندرو وايت 3    |       2        |   steve rogers   |   ستيف روجرز 

here mysql statement:

$querystring =  "(select contact_name, contact_name_arabic                             contacts                             contact_name '%".$querystring."%'                              or contact_name_arabic '%".$querystring."%')                             union                             (select company_name, company_name_arabic                             companies                             company_name '%".$querystring."%'                              or company_name_arabic '%".$querystring."%')"; 

thanks!

try query in mysql query builder

(select contact_name, contact_name_arabic                             contacts                             contact_name '%e%'                              or contact_name_arabic '%e%')                             union                             (select company_name, company_name_arabic                             companies                             company_name '%e%'                              or company_name_arabic '%e%') 

if working check value comes in variable $querystring.

and not need check field company_name_arabic

(select contact_name, contact_name_arabic                                 contacts                                 contact_name '%e%')                                 union                                 (select company_name, company_name_arabic                                 companies                                 company_name '%e%' )