diff --git a/identify-slow-queries.md b/identify-slow-queries.md
index 0962505d3ea8d..b9722d3b5ee16 100644
--- a/identify-slow-queries.md
+++ b/identify-slow-queries.md
@@ -136,7 +136,7 @@ TiKV Coprocessor Task fields:
 * `Cop_wait_max`: The maximum waiting time of cop-tasks.
 * `Cop_wait_addr`: The address of the cop-task whose waiting time is the longest.
 * `Rocksdb_delete_skipped_count`: The number of scans on deleted keys during RocksDB reads.
-* `Rocksdb_key_skipped_count`: The number of deleted (tombstone) keys that RocksDB encounters when scanning data.
+* `Rocksdb_key_skipped_count`: The number of keys, excluding tombstone keys, that RocksDB encounters when scanning data.
 * `Rocksdb_block_cache_hit_count`: The number of times RocksDB reads data from the block cache.
 * `Rocksdb_block_read_count`: The number of times RocksDB reads data from the file system.
 * `Rocksdb_block_read_byte`: The amount of data RocksDB reads from the file system.