Zabbix low level discovery trigger dependencies

There is NO such thing in Zabbix LLD,

so there is workaround, 

create a trigger that has double check.

for example, i want to have two severities for filesystem discovery(hdd size).

If there is less than 5GB, severity High, and if there is less than 2gb severity Disaster.

for 5GB we create double check, first is to check if there is less than 5GB and second to check if there is more than 2GB, and finished trigger should look like this:

Tittle: Free disk space is less than 5GB on volume {#FSNAME} ({ITEM.VALUE2})

Expression: {Template OS Windows:vfs.fs.size[{#FSNAME},free].last(0)}<5400000000 & {Template OS Windows:vfs.fs.size[{#FSNAME},free].last(0)}>2148000000 & {Template OS Windows:vfs.fs.size[{#FSNAME},free].last(0)}

Severity: High

For 2Gb check:

Title: Free disk space is less than 2GB on volume {#FSNAME} ({ITEM.VALUE2})

Expression: {Template OS Windows:vfs.fs.size[{#FSNAME},free].last(0)}<2148000000 & {Template OS Windows:vfs.fs.size[{#FSNAME},free].last(0)}

Severity: Disaster