I'm fighting with the Caml Query which returns zero items:
<View>
<Query>
<Where>
<And>
<Eq>
<FieldRef Name="Dokumenttyp"/>
<Value Type="Text">Fahrtspesen</Value>
</Eq>
<And>
<Geq>
<FieldRef Name="ExportiertAm"/>
<Value Type="DateTime">2017-08-12</Value>
</Geq>
<Lt>
<FieldRef Name="ExportiertAm"/>
<Value Type="DateTime">2017-08-13</Value>
</Lt>
</And>
</And>
</Where>
</Query>
</View>
What I do not understand, the following two return something. The first returns many items (one of these is the one with ID 290) and the second one returns two items (the 290 and the 291).
<View>
<Query>
<Where>
<Eq>
<FieldRef Name="Dokumenttyp"/>
<Value Type="Text">Fahrtspesen</Value>
</Eq>
</Where>
</Query>
</View>
<View>
<Query>
<Where>
<And>
<Geq>
<FieldRef Name="ExportiertAm"/>
<Value Type="DateTime">2017-08-12</Value>
</Geq>
<Lt>
<FieldRef Name="ExportiertAm"/>
<Value Type="DateTime">2017-08-13</Value>
</Lt>
</And>
</Where>
</Query>
</View>
Based on the results of the latter two, shouldn't the first one return something?

290.