會計文員和採購員那一種行業好些呢?

I personally think accounting has much more job opportunity and future than the buying job sector. You have 2 years' accounting experience already better than starting from scratches. Think of the short-term award relative to the long-term income and future. Moreover, the accounting jobs are quite demanding. Not every company needs a purchasing personnel but every company needs accounting personnel. You can study accounting to upgrade yourself to become a professional accountant. Your future career is then with much brighter outlook and wider choice than working as a purchasing personnel. Long-term career development and advancement leading to higher reward should prevail.