SELECT 
  feature_id, 
  variant_id, 
  value, 
  value_int 
FROM 
  cscart_product_features_values 
WHERE 
  product_id = 8295 
  AND lang_code = 'en'

Query time 0.00052

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_features_values ref lang_code,product_id,product_id_idx,product_feature_idx product_id 3 const 96 Using where

Result

feature_id variant_id value value_int
30 6131
176 6262
127 5895
128 5899
129 5903
136 5976
176 6267
176 6268
176 6265
135 5971
24 107
176 6266
136 5975
136 5977
136 5973
176 6269
136 5974
176 6260
176 6259
176 6264
176 6270
178 6317
176 6271
176 6263
176 6261
176 6272