I have done this way.
I have 2 custom objects- Test1__c and Test2__c . To consolidate those under one tab ABC with standard view (same listview look if I set test1 and Test2 in customobject tabs) , I have written a VF page ABC and set as VF tab-
this is code for VF Page ABC.

<apex:tabPanel selectedTab="tab1" tabClass="activeTab" inactiveTabClass="inactiveTab">
 <apex:tab label="サイト設定情報" name="tab1" >
<iframe scrolling="yes" frameborder="0" allowtransparency="true" src="/apex/Test1Tab" style="width: 100%; height: 800px;" title=""></iframe>
</apex:tab>
<apex:tab label="コンバージョン関連データ確認" name="tab2">
<iframe scrolling="yes" frameborder="0" allowtransparency="true" src="/apex/Test2Tab" style="width: 100%; height: 800px;" title=""></iframe>
</apex:tab>
</apex:tabPanel>

</apex:tabPanel>

Now say for Test1Tab this is VF page.

<apex:page showHeader="false" standardController="Test1__c ">
<apex:sectionHeader title="Test1" subtitle="Home" />
<apex:listViews type="Test1__c " />
</apex:page>

 Now my Test1 and Test2 are coming under ABC. But when from standard listview of Test1__Cc under ABC, I am clicking Edit/New then its going out of tab and directs to conventional main text1__c edit/new page. 

So what is to do to load Edit/new page also under ABC. 

Thanks in advance.