[Bug]: [restful v2]The search api does not support nq>2. It can only return the top k results for a single query when nq > 1.

[zhuwenxing]

Is there an existing issue for this?

• [X] I have searched the existing issues

Environment

- Milvus version:master/2.4
- Deployment mode(standalone or cluster):
- MQ type(rocksmq, pulsar or kafka):    
- SDK version(e.g. pymilvus v2.0.0rc2):
- OS(Ubuntu or CentOS): 
- CPU/Memory: 
- GPU: 
- Others:

Current Behavior

The search api does not support nq>2. It can only return the top k results for a single query when nq > 1.

Expected Behavior

No response

Steps To Reproduce

No response

Milvus Log

No response

Anything else?

No response

[yanliang567]

/assign @PowderLi /unassign

[PowderLi]

whatever how many nq in the http request's Data, milvus restful server only send one SearchRequest to grpc server, and return the SearchResults need i do some extra things with the SearchRequest & SearchResults /assign @czs007

where	what	nqs	topk
http client	send http request	Data	Limit
milvus restful server	transfer to grpc search params	PlaceholderGroup	SearchParams
milvus grpc server	return SearchResultData	[]*FieldData	TopK

[PowderLi]

/assign @zhuwenxing

[zhuwenxing]

verified and fixed. test cases added to ci and passed https://github.com/milvus-io/milvus/pull/33456

but all results were also flattened as https://github.com/milvus-io/milvus/issues/32420