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SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (18, 186, 179) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00029

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_product_descriptions	range	PRIMARY,product_id	PRIMARY	9		3	Using index condition

Result

product_id	meta_keywords	search_words	promo_text
18	3D Blu-ray Disc™ Player, BD-D7000, 3D-воспроизведение, Blu-ray, Blu-ray Disc, Blu-ray плеер, плеер, 3D, Full HD, HDMI, USB, DLNA, Smart Hub, интернет-приложения, веб-браузер, Wi-Fi, Ethernet, медиаплеер, мультимедиа, кино, домашний кинотеатр, аудио, видео	3D Blu-ray Disc™ Player (BD-D7000): - 3D Blu-ray плеер - BD-D7000 - Blu-ray плеер - 3D плеер - BD-D7000 плеер - Blu-ray Disc плеер - 3D Blu-ray плеер BD-D7000
179			<p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>
186			<p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>