Lost my Manual,where I do connect that speaker wire behind that speaker base?

Usually you will plug the little speakers into the big speaker, and then plug your big speaker into the computer - usually the green plug in on the back of the computer. It might also be a USB plug. If it is a USB plug, then you will have to download a driver from the companys website for that specific model - usually found in the Support section. After you install, you might have to reboot your computer.

Also, make sure you plug the power for the speakers into the wall and turn on any power buttons. Some speakers have a volume control on them. Make sure this is turned up and then make sure your computer volume is turned up (check this through: Control Panel > Sound and look at the levels and settings there. Also, under playback devices make sure that your speaker jack you have them pluged into is set as the default.

Hope this helps.