Myoril is the brand name; the medicine it contains is called thiocolchicoside. It is not sold in most developed countries such as US, UK, Ireland, Australia etc. It should not be taken by breast-feeding women.
I do not know why Etoxib (etoricoxib) was given to the patient. Its use during breast-feeding is prohibited. For aches and pains, the safest drug during lactation is paracetamol (such as Crocin).