I have made a wireless robot with ht12d/e and l293 ic and i have used two type of motors. first motor(plastic geared) was working ok with l293(i.e it was working at 1A) second motor(johnson geared motor) was not working with l293 but worked well when i connected it to ac power adapter. further i got to know that johnson motor works at 10A so is there any way to amplify the output current of l293 upto 10A or to make a differentrf circuit for running the motor.
I think amplifying the output of L293 would be unusual. Just build or buy a beefier H-bridge; maybe 15A to be on safe side, e.g. this Pololu board uses a controller and external FETs.
You can also find single-package versions. You'll want to look at the automotive section of the IC manufacturers websites, they usually have something high-power there, e.g. ST has a 30A VNH3SP30-E. They also have max 12A VNH7100AS. The datasheet of this one is a bit confusing. It has an internal current limiter and auto-shutdown function, so the max load current isn't given in the absolute ratings table... but in the protections table; it seems you can get at least 12A out of it with proper cooling. On the plus side, it will be harder to bust in use because of its shutdown functions.
They also have a very similar VNH7070AS, which has the min limit current set to 15A. I'm pretty sure you can find similar products by other IC manufacturers.
You could also build a fairly beefy H-bridge with discrete bipolar transistors, e.g. as shown in this tutorial for a max 10A one, e.g. using the TIP14x. But it will be more inefficient than MOSFET-based ones, i.e. it will waste more power as heat and you'll have to worry more about cooling it. On the plus side, bipolar transistors usually are cheaper than MOSFETs for a given power rating.
See also related question: Commanding a 12V DC motor with high power (~20A)