hello

am working on a pharmacy project ,

they have some product sold in different uom from pos so i used  this module

https://www.odoo.com/apps/modules/10.0/pos_multi_uom/

but its not gives me the best solution

my problem is:

if i have from product x ( 2 unit , 8 capsules )  and it sold in units and capsules 

if i sell 1 unit it deceased 1 from inventory so it should be like this  ( 1 unit , 8 capsules )

in the qty : 1.8

and if i choose to sell this product in capsules it should decreased 0.1 so  it should be like this ( 1 unit , 7 capsules )

in the qty : 1.7

 my question is : 

can any one help me to edit the UOM ratio to give me the best answer ?