/c jmp [esp]
search for asm code matching the given string
/c instr
search for instruction 'instr'/ce esil
search for esil expressions matching substring/ca instr
search for instruction 'instr' (in all offsets)/c/ instr
search for instruction that matches regexp 'instr'/c/a instr
search for every byte instruction that matches regexp 'instr'/c instr1;instr2
search for instruction 'instr1' followed by 'instr2'/c/ instr1;instr2
search for regex instruction 'instr1' followed by regex 'instr2'/cj instr
json output/c/j instr
regex search with json output/c* instr
r2 command output
/ce /ca /c/ /c/a /cj /c/j /c*