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Tamiya Twin gearbox and UDN2993B motordriver

I've got a timaya twin motor gearbox #70097 and a UDN2993B motordriver ic bought on ebay(http://www.allegromicro.com/en/Products/Part_Numbers/Archive/2993.pdf)

First I recieved the motordriver and connected it to a some motor i found in the garage. It worked but when i received my twin motor gearbox and connected it, it didn't worked. Even on 5volt the motors wont work but connecting them directly to the power source they work fine.

Why does these motors not work for this motordriver and what motordriver do i need?

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First, that chip cannot carry enough current to drive those motors. It states 500 mA, and those motors draw a lot more, and will fry that chip. Second, the chip won't just "drive" the motors by itself. The enables and phase and load supply and logic supply pins all need to be connected. A replacement motor that runs better than the stock Tamiyas with less current is available, but still technically beyond that h-bridge IC.
Second, the motor power operating voltage (VBB) for the UDN2993B should be between 10..30V. It ist not made for 5V. The Polou LVDSMC will do the job, or look at Oddbots motor controller for Mr. Basic

it does run an other motor on 5v...

i was looking for a single ic to run both motors, are there other options, i need something that can ouput 2A?

Maybe it does run with 5V but this is out of the chip specification.

A L298 with good cooling is maybe an option. But you need external clamp diodes for this. 5V is also a bit out of specification for the L298, should be 2.5V higher. Another idea stack 3 or 4 L293D chips or use 2 stacked L293D with one motor.