Advanced weapons include precise missiles, surface to air missiles and air defenses transported mostly via Damascus airport which has come under repeated strikes attributed to Israel
As the U.S. was supplying Israel with military aid, so is Iran delivering weapons to its regional allies, in transports through the Damascus airport mostly, while other weapons transports arrive through other locations.
The frequent strikes on Syria in recent days, attributed to Israel, were for the most part intended to thwart such transfers from Iran, that were meant to increase the number of precise missiles, anti-tank missiles and air defenses including the Iranian made surface to air 358 missiles also called SA-67) that can intercept drones, planes low flying aircraft and missiles, available to Hezbollah.
Iran had already supplied its Lebanese proxy with a substantial stock of missiles which have been used by Hezbollah against Israeli drones recently but have thus far failed to shoot any down. Israel has been able to intercept the 358 missiles using its air defenses.
Seems like the root many of the problems in the middle east pretty much all lie with Iran, especially its murderous elders who donate weapons and train various paramilitary and terrorist organizations. Seems like a huge thorn in the side for that entire region.