When I try to export some vector data in KML, I sometimes "lose" some vectors. It depends on the way layers are created :
case #1 : no tags are created. All vectors are considered "at the top level". Everything is fine
case #2 : vectors all belong to a specific layer, using one or several tags. Everything is still fine
case #3 : some vectors do not belong to a specific layer. Others belong to specific layers. The "top level" vectors are not seen by GDAL (not displayed in QGIS either). However, they are displayed in Google Earth.
The KML file looks like :
<kml> <Document> <name>snafu</name> <Placemark>...</Placemark> <-- Not "seen" by ogrinfo
<Folder id="123456""> <Placemark>...</Placemark> <-- OK
My environment : Windows 8 64 bits, Gdal 2.0.2, using LIBKML plugin.