Try to clarify filter docs
The `filter` command allows you to create a new ontology from a source ontology by copying only the selected axioms. The `remove` command is the opposite of `filter`, allowing you to remove selected axioms. `filter` accepts the same options as `remove` and processes them in the same order. See [`remove`](/remove) for details on configuring the options.
-By default, `filter` will include all axioms from the input ontology that contain *one or more* entities from the specified set. To be more strict and only include axioms in which *all* entities in the axiom are in the specified set, use `--trim true`.
+Each axiom refers to one or more entities: classes, object properties, annotation properties, etc. By default, `filter` will copy axioms from the input ontology for which *all* the entities are in the specified set. To be more relaxed and copy axioms that contain *one or more* entities from the specified set, use `--trim false`. This will usually leave some "dangling references" to entities that were not in the specified set.
This operation maintains structural integrity; lineage is maintained, and gaps will be filled where classes have been excluded. If you wish to *not* preserve the hierarchy, include `--preserve-structure false`.
## Annotations
-The `filter` command also includes a special `--select "annotations"` option. If this is included, all annotations on filtered terms will be included, regardless of if those properties are in the set of terms or not.
+The `filter` command also includes a special `--select "annotations"` option. If this is included, all annotations on filtered terms will be copied, regardless of if those properties are in the set of terms or not.
The following command will only return `OBI:0000070` with just a label annotation:
```
