wock is the slang for Codeine, a cough syrup which can be used to lean. When Lil' Yatchy wrote the lyrics "I took the wock to Poland", he porously emphasized the O syllable in wock to make it sound like the word walk; implying that he walked to bring wock to Poland. If you listen closely, you'll notice that he used vibrato when saying wock/walk which also implies that the walk he took was shaky (because of lean).
thx!!!