Ошибка поиска в админке

Если в поле поиска по админке написать 0 и нажать поиск (значок лупы) - Sorry, service is temporarily unavailable.

Tygh\Exceptions\AException

Message
The table '_search' is full (1114)INSERT INTO _search (id, object, sort_field) SELECT cscart_orders.order_id, 'orders', cscart_orders.order_id FROM cscart_orders as cscart_orders  LEFT JOIN cscart_users as issuers ON issuers.user_id = cscart_orders.issuer_id LEFT JOIN cscart_order_docs as invoice_docs ON invoice_docs.order_id = cscart_orders.order_id AND invoice_docs.type = 'I' LEFT JOIN cscart_order_docs as memo_docs ON memo_docs.order_id = cscart_orders.order_id AND memo_docs.type = 'C' WHERE 1  AND cscart_orders.is_parent_order != 'Y'  AND cscart_orders.status != 'N' GROUP BY cscart_orders.order_id

Error at
app/Tygh/Database/Connection.php, line: 1136

Backtrace
File:app/Tygh/Database/Connection.php
Line:500
Function:throwError

File:app/functions/fn.database.php
Line:133
Function:query

File:app/functions/fn.search.php
Line:198
Function:db_query

File:app/controllers/backend/search.php
Line:29
Function:fn_search

File:app/functions/fn.control.php
Line:669
Function:include

File:app/functions/fn.control.php
Line:427
Function:fn_run_controller

File:artadmin.php
Line:27
Function:fn_dispatch

на демке не воспроизводится, как я полагаю, из за гораздо меньшего количества записей? В моей базе порядка 8000 товаров, 27000 заказов и 10000 покупателей

Скорее всего ошибка возникает из-за ограничения на размер временных таблиц на вашем сервере. Попробуйте увеличить значения:

tmp_table_size
max_heap_table_size