He bicycled with his medicine all over the island, and came in contact with the various customs of each locale.
三個月結業後，吳樂天騎著腳踏車，載著藥箱，當起了賣藥郎。推銷藥，嘴皮子自然要「溜」。兩年下來，他練就了一套「嘴上功夫」，還藉著賣藥的機會，踏遍了全台灣各角落，接觸到各地的民情風俗。