Update graphql search doc.mdx (#989)

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Author: rakeshjosh2003

docs/api/graphql/search.mdx

@@ -20,3 +20,7 @@ src search -json 'repo:pallets/flask error'
 ```
 
 You can then consume the JSON output directly, add `--get-curl` to get a `curl` execution line, and more. See [the `src` CLI tool](https://sourcegraph.com/github.com/sourcegraph/src-cli) for more details.
+
+## Incomplete search results when using Graphql
+
+Sometimes, users find discrepancies in the number of results returned on UI compared to Graphql for the same query. This can be avoided by adding ```"count:all" ``` to the query used in Graphql. This ensures all the matching records are being fetched via Graphql.