Wall on the street side shows damp spots

Hello, I am Milan and new here. I already have a question because I haven't found anything about my problem here. My house is located directly on the street. When it rains and cars drive through puddles, the water splashes onto my house wall. The second issue is that my house, specifically the living room, is about 45 cm lower than the street. The walls are approximately 70 cm thick with a lot of stone or rock. Now, a few damp spots have appeared on this side, and my question is how you would waterproof it. Digging from the outside is difficult because the street is directly adjacent to the house. I have applied a fillet joint from the outside that helped before but no longer this year. Would it help to remove the fillet joint and pour a few buckets of sealant downward, something liquid enough to flow about 0.5 m down and seal, and then reapply the fillet joint? What do you think, would that work? Thanks in advance, Milan.

Hi Milan,
take some photos and post them here. Both from the outside and from the inside. At what height does the wall get damp from the inside in relation to the outside.

Would it help to remove the cove joint and let a few buckets of sealing agent run downwards

No, that doesn’t work.

Digging out from the outside is difficult because the street borders directly on the house,

Well, usually that is the only really effective solution...

Good morning and sorry for the late reply. Attached are the pictures, inside you can see that the moisture is indeed where the wall sinks 40-50cm into the street.

Open the street, seal the wall, be happy. Yes, it won’t be cheap.

Open up the street, seal the wall, be happy. Yes, it won't be cheap.

Insulating from the inside really wouldn't help, there are good materials nowadays, right?