Why not now focus on the Thai big blue chip stocks?

Because these are often in the often over-rated service sector like Telecom, Banks & Energy; not exports, tourism or domestic consumption and manufacturing which Thailand is competitive at.  Most larger capitalized stocks are relatively expensively valued and so often pay lower dividends yields.  However since year 2001 we have pointed out a few select large capitalized stocks as well, or recent for example PTTGC one of the highest dividend stocks on the SET.  However overall, I prefer select smaller cap shares as they are often undervalued, have faster growing earnings and pay higher dividends.  Why should smaller capitalize Thai growth companies sell at the discount to the market p/e? Even while many pay higher then SET averaged dividends and have stronger long term  growth rates.  Since 2017 however smaller and mid cap stocks have underperformed the SET this is in large part due to Thai retail investors less participation.  But this changed since April 2020 and have since taken the lead by outperforming the SET since by a large margin.  Since May 2021, for example, I wrote more about Thai Optical Group (TOG) here then any other stock.  A small cap stock which just about doubled since, vs. barely +15% up for the SET last year.  (January 2 2022).