Fetch fields on select value of link field

I have two doctypes 1)Asset Type and 2)Assets.
In ‘Asset Type’ I added two fields ‘Asset Type Name’ and second is a dependent field if the asset type name is ‘Laptop’ then show field ‘RAM’ which is a select field.
Now I added link field of ‘Asset Type’ doctype in ‘Assets’ doctype and added fields like (asset name, asset type name).
I want like if in ‘Assets’ form I select ‘Asset Type Name’ as ‘Laptop’ then add field ‘RAM’ with its options which I added earlier in ‘Asset Type’ doctype.