[role="xpack"]
[[maps-search]]
== Searching your data

The **Maps** application embeds the query bar for real-time ad hoc search.
Only layers requesting data from {es} are filtered when you submit a search request.

You can create a layer that requests data from {es} from the following:

* <<vector-layer>> with:

** Documents source

** Grid aggregation source

** <<terms-join>>

* <<heatmap-layer>> with Grid aggregation source

[role="screenshot"]
image::maps/images/global_search_bar.png[]


[role="xpack"]
[[maps-layer-based-filtering]]
=== Filtering a single layer

You can apply a search request to individual layers by setting `Filters` in the layer details panel.
Click the *Add filter* button to add a filter to a layer.


[role="screenshot"]
image::maps/images/layer_search.png[]

[role="xpack"]
[[maps-search-across-multiple-indices]]
=== Searching across multiple indices

Your map might contain multiple {es} indices.
This can occur when your map contains two or more layers with {es} sources from different indices.
This can also occur with a single layer with an {es} source and a <<terms-join>>.

Searching across multiple indices might sometimes result in empty layers.
The most common cause for empty layers are searches for a field that exists in one index, but does not exist in other indices.
Add {ref}/mapping-index-field.html[_index] to your search to include documents from indices that do not contain a search field.

For example, suppose you have a vector layer showing the `kibana_sample_data_logs` documents
and another vector layer with `kibana_sample_data_flights` documents.
(See <<add-sample-data, adding sample data>>
to install the `kibana_sample_data_logs` and `kibana_sample_data_flights` indices.)

If you query for
--------------------------------------------------
machine.os.keyword : "osx"
--------------------------------------------------
the `kibana_sample_data_flights` layer is empty because the index
`kibana_sample_data_flights` does not contain the field `machine.os.keyword` and no documents match the query.

[role="screenshot"]
image::maps/images/global_search_multiple_indices_query1.png[]

If you instead query for
--------------------------------------------------
machine.os.keyword : "osx" or _index : "kibana_sample_data_flights"
--------------------------------------------------
the `kibana_sample_data_flights` layer includes data.

[role="screenshot"]
image::maps/images/global_search_multiple_indices_query2.png[]