```xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns4:query_definition xmlns:ns2="http://www.i2b2.org/xsd/cell/crc/psm/1.1/" xmlns:ns4="http://www.i2b2.org/xsd/cell/crc/psm/querydefinition/1.1/" xmlns:ns3="http://www.i2b2.org/xsd/cell/crc/psm/analysisdefinition/1.1/">
    <query_name>Exter-Assau-Assau@23:55:54</query_name>
    <query_timing>ANY</query_timing>
    <specificity_scale>0</specificity_scale>
    <panel>
        <panel_number>1</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>0</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>0</hlevel>
            <item_name>(PrevQuery)External causes@23:41:16</item_name>
            <item_key>masterid:28357</item_key>
            <tooltip>External causes@23:41:16</tooltip>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
    <panel>
        <panel_number>2</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>0</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>0</hlevel>
            <item_name>(PrevQuery)Assault by cras@19:55:01</item_name>
            <item_key>masterid:28320</item_key>
            <tooltip>Assault by cras@19:55:01</tooltip>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
    <panel>
        <panel_number>3</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>1</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>0</hlevel>
            <item_name>(PrevQuery)Assault by blun@22:39:01</item_name>
            <item_key>masterid:28338</item_key>
            <tooltip>Assault by blun@22:39:01</tooltip>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
</ns4:query_definition>

```

I want to find all records where the patient has a history of external causes (such as accidents, injuries, or poisonings) and has experienced an assault by crash (e.g., car accident) but not an assault by a blunt object (e.g., a fist or a bat). The timing of these events is not important, and I want the query to be as accurate as possible.