I'm working on the same issue.

Tip: Start here: Odoo 10.0\server\odoo\addons\base\security\base_security.xml

Here you may see interesting code:

    <record model="ir.rule" id="res_partner_rule">
            <field name="name">res.partner company</field>
            <field name="model_id" ref="model_res_partner"/>
            <!--
                Show partners from ancestors and descendants companies
                (or company-less), this is usually a better default for
                multicompany setups.
            -->
            <field name="domain_force">['|','|',('company_id.child_ids','child_of',[user.company_id.id]),('company_id','child_of',[user.company_id.id]),('company_id','=',False)]</field>
            <field name="active" eval="False"/>
        </record>

Also you might find it useful: https://www.odoo.com/forum/how-to/developers-13/setting-up-rules-access-right-in-xml-csv-files-12667

You can use Odoo access rules feature to achieve that.Also you can inherit search method for the objects and you can use the domain based on your requirement at the method to have the functionality.

Hi,

This would help.

<record id="current_company_vendors" model="ir.rule">

        <field name="name">Current Company Partners</field>

        <field name="model_id" ref="base.model_res_partner"/>

        <field name="global" eval="True"/>

        <field name="domain_force">['|',('company_id','child_of',[user.company_id.id]),('company_id','=',False)]</field>

    </record>

Regards,

Bought some books about Odoo.. but still didn't get an manual for creating such a thing :/