Update README.md

Author: yaboo-oyabu

00_Miscellaneous/text-similarity-analysis/README.md

@@ -68,7 +68,7 @@ If you've followed the instruction in previous section, you should have reuter d
 export FILE_PATTERN=$BUCKET/reuters
 ```
 
-You should also set name of BigQuery dataset and table so Dataflow pipeline can output the feature embeddings to the right place in BigQuery.
+Note that you have to create BigQuery dataset before running Dataflow job. You should also set name of BigQuery dataset and table so Dataflow pipeline can output the feature embeddings to the right place in BigQuery.
 
 ```bash
 # Information about output table in BigQuery.