There are a lot of things that can make it run lean.
I always shudder when some one says they have cleaned the carb on a hand held.
I do this professionally and I have problems with them some times having to do the job 3 or 4 times till I get a satisfactory result.
However there is a heiracy of tests to do before you rip into the carb.
Even then you can still get some erronious results.
So we start by spraying some starter fluid down the carb and see if it starts while also watching the inline spark tester.
If it does not start and there is no little flashes then the problem is electric so you are 1/2 way home.
If it does start then you try to keep it running with very short burst of starter fluid.
If it passes this test then you rig up a seperate fuel line and try again.
Runs OK then problem in the fuel tank, fuel filter, fuel lines or fuel pump.
Don't run then then you look at crankcase & cylinder pressure & vacuum.
It is next to impossible to diagnose small hand helds over the web, come to think of it , diagnosing them in the workshop aint that easy either.
Assuming that you properly cleaned cecked the carb was working properly then you can go wo ways.
Do a flow test by pulling the carb off and blowing some air through it, watching for a continious spray of fuel as the throttle is opened up wide.
or
Rig up a temporoay fuel supply high above the trimmer so it will gravity feed the carb
