The Il-38 is a militarized version of the Il-18, which was broadly similar to the Lockheed Electra, but the Il-18 flew slightly before the Electra, had a longer production run, and a more successful commercial career.
I’m pretty sure those doors are for weapons and/or sonobouys, since everything I can find mentions the Il-38 fitting all of its’ sensors into either a radome and FLIR turret under the nose, the MAD boom on the tail, or box-like fairing fitted over the forward fuselage on some examples.