I think my TL has oil leak under engine.
what liquid is yellow thing in picutre ?

 

grease that mixed with water, the grease come from your axle boot. Its time for a new axle.

 

it could be the axle boot or the oil filter housing or another gasket in the area. A mechanic will clean the area and see where the drip is originating from.

 

Mine was the gasket around the water pump.
So I had that and the timing belt changed out.
Also the motor mount.
$1,232

 

I see several types of leaks there and there are many potentials in that area:
- oil pump
- VTEC solenoid/oil filter housing
- the yellow stuff looks like coolant mixed with oil/grease
- axle grease
- power steering fluid -> there is a metal to rubber hose connection there that's prone to leak

You need to fix one, clean it up completely, drive again and fix the next leak until you get all of them fixed.

 

My suggestion would be to clean it all up first, preferable with a pressure washer. It could be any or all of the issues listed by t-rd above, or even other leaks not mentioned. I was going to say rear main crank seal but diagnosis is a crap shoot without cleaning then observing...