This one is too far gone to explain... basically, it's "What do you call catfish with a burr/rhotacism?" "Catfish" is "Harcsa" and people speaking with burr tend to pronounce "L" instead of "R". So "Harcsa" becomes "Halcsa", and "Hal" is "Fish" in Hungarian. But there's no R in catfish, so this one is a wash...
Two figures emerge from the forest. One is running, the other is bearing. This one is extra nonesense in English.... The joke is based on conjugation. "FutVA" is a version of "running" in Hungarian, referring to how someone is moving. With the "va" at the end, it means someone is emerging from the forest while running. Meanwhile, "bear" is "medve" in Hungarian, with a similar sounding conjugation at the end: "ve". However, this one is a simple coincidence, so the joke plays on the other figure emerging while being a bear.
At a petrol station. - How much does one drop of oil cost? - One drop? That's free. - Great! Please fill it up with 40 liters worth of drops for me.
Samurai goes into a shop. - Give me a bag. - No bag. (In Hungarian: "Nincs" and "Zsák", literalli "None" and "Bag", which said out loud sounds like "ninjas") - Ninjas? Where?