By A Web Design
The in-built, Joomla, Search module searches only within Joomla content. It does not search through appropriate areas of VirtueMart like its product catalog.
To test this, in the Joomla frontend Search box, type in a product name as shown in Diagram 1. Then press Enter to display the search result.

Diagram 1
The search result would display zero results for the searched for word (i.e. product name) as shown in Diagram 2. This means that Joomla’s default search does not access appropriate areas of VirtueMart.

Diagram 2
VirtueMart provides a module (mod_virtuemart_search_1.1.5.j15) and plugin (vmxsearch.plugin_1.1.5.j15) in the complete installation package of VirtueMart.
mod_virtuemart_search_1.1.2.j15 is the search module for VirtueMart. When you install and publish this module in Joomla, visitors will be able to search the VirtueMart product catalog only.
vmxsearch.plugin_1.1.2.j15 is the search plugin which enables Joomla’s default search system to access the VirtueMart catalog areas. When this plugin is installed and enabled, Joomla's standard search module can locate VirtueMart products as well.
In other words, The "VirtueMart Extended Search Plugin" i.e. vmxsearch.plugin_1.1.2.j15 is designed to allow you to search for VirtueMart products using the Joomla’s built-in search system. This plugin allows you to use the Joomla built-in search system for both the website and VirtueMart. Hence, it is definitely preferable to use VirtueMart Search plugin on any Joomla driven website that carries a VirtueMart shopping cart.
This tutorial, explains how VirtueMart Search Module and Plugin are implemented in VirtueMart.
To setup the VirtueMart search module and plugin in Joomla, login to Joomla as administrator, by simply entering the url_of_your_website/administrator in your Browser. Enter the appropriate username and password {which was provided while installing Joomla} and then click on Login as shown in Diagram 3.

Diagram 3
After logging in as Joomla Admin, a Control Panel page opens as shown in Diagram 4. The Control Panel provides access to different Joomla functions and features.

Diagram 4
In the top menu, locate the link Extensions. Click on Extensions. From the drop down menu that appears click on Install/Uninstall as shown in Diagram 5.

Diagram 5
An Extension Manager page opens. In the Upload Package File section, click the Browse button as shown in Diagram 6.

Diagram 6
After clicking on the Browse Button a file navigator window opens. Navigate to the appropriate folder where the downloaded files are and select VirtueMart Search Module then VirtueMart Search Plugin, one at a time and Upload the file and install them into the Joomla framework. Details of this are given in the material below.
Navigate from VirtueMart complete installation package folder to modules folder via the file browser that opens up. Select and Open the module zip file (mod_virtuemart_search_1.1.5.j15.zip) from there as shown in Diagram 7.

Diagram 7
The zip file name appears in the Package File text box as shown in Diagram 8. Then click the Upload File & Install button.

Diagram 8
Once the file has been uploaded you will see the successful installation message as shown in Diagram 9.

Diagram 9
In the top menu, locate the link Extensions. Click on Extensions, from the drop down menu that appears click on Module Manager, in order to activate the module on the frontend as shown in Diagram 10.

Diagram 10
A list of modules in Module Manager is displayed. From the list of Module Name, locate the VirtueMart Search module. Click on that module to edit the configuration as shown in Diagram 11.

Diagram 11
Change the following configuration settings of module in this screen:
Enabled: Yes
Position: [desired location] (In this case the Position is Left)
Menu Selection: [desired menu on which it is to be displayed] (In this case the Menu Selection is Shopping Cart).
Now you're done. Just click on Save/Apply, to make sure the changes are stored as shown in Diagram 12.

Diagram 12
The VirtueMart Search module would be successfully activated (enabled) as shown in Diagram 13.
You’ve just activated the VirtueMart Search module on the Joomla frontend.

Diagram 13
To view this, in the frontend of the website, Click on the Shopping Cart link in the Main Menu as shown in Diagram 14.

Diagram 14
The VirtueMart Search module would be displayed on the specific location of website as shown in Diagram 15.

Diagram 15
In the Search module text box, type the product name and click on Search button as shown in Diagram 16.

Diagram 16
According to the keyword type in the VirtueMart search box, the product details will be displayed as a search result as shown in Diagram 17.

Diagram 17
This is how the VirtueMart Search module works in Joomla.
The VirtueMart search plugin is not dependent on VirtueMart search module. It is not necessary to install module for this plugin to work.
Install the plugin through Extensions -> Install/Uninstall (the same as search module installation).
Navigate to the VirtueMart complete installation package folder. From there to the plugins folder via the file browser that opens up. Select and Open the plugin zip file (vmxsearch.plugin_1.1.5.j15.zip) from there as shown in Diagram 18.

Diagram 18
Once the file has been uploaded you will see the successful installation message as shown in Diagram 19.

Diagram 19
In the top menu, locate the link Extensions. Click on Extensions, from the drop down menu that appears click on Plugin Manager, in order to activate the plugin as shown in Diagram 20.

Diagram 20
The Plugin Manager displays list of plugins. From the list of Plugin Names, locate the VirtueMart Extended Search Plugin. Click on that plugin to edit the configuration as shown in Diagram 21.

Diagram 21
Set Enabled to “Yes”.
Now you're done. Just click on Save/Apply, to make sure the changes are stored as shown in Diagram 22.

Diagram 22
The VirtueMart Extended Search Plugin will be successfully activated (enabled) as shown in Diagram 23.

Diagram 23
In Joomla frontend, type the product name as keyword into the Joomla standard search box as shown in Diagram 24. After entering the search keyword, press Enter to display the search result.

Diagram 24
According to the keyword type in the Joomla search box, the search result will be displayed as shown in Diagram 25.

Diagram 25
This is how the VirtueMart Search plugin extends the default Search system of Joomla CMS.