Item conversion factor filter

hi all.
in sales invoice when add item in child table. item uom is display all uom in database. but i want to filter item uom dropdown list to display conversion factor uom of item only.
example item a001 product1
conversion factor uom = gram , conversion factor = 1
kilogram, conversion factor = 100

i want to filter uom dropdown list for gram and kilogam only.

help me pls.
many thank.

Did you find the solution ?