text: At most 5 answers will be returnedmax_extractive_segment_count - The maximum number of extractive segments returned in each search result.
  Currently one segment will be returnedfilter - The filter expression that allows you filter the search results based on the metadata associated with the documents in the searched data store. query_expansion_condition - Specification to determine under which conditions query expansion should occur.
  0 - Unspecified query expansion condition. In this case, server behavior defaults to disabled.
  1 - Disabled query expansion. Only the exact search query is used, even if SearchResponse.total_size is zero.