reporting services - Only show a subreport if it returns data -

i have subreport in tablix row want show if there data, because when subreport doesn't return anything, blank line. how can fix this? not want blank line show.

go gray block of row , right click go 'row visibility' , there go show or hide based on expression , expression should like: =iif(isnothing(your field.value),true,false)