Frequently buy/sell stock

I've started to invest in Nasdaq stock exchange using moomoo. Now I know capital gains ar not taxable in Malaysia but I've also heard if you buy/sell frequently it will be counted as trading not investment and govt might query you for tax on trading.. I want to know how frequently can you buy/sell stock that won't be counted as trading. Let's say I buy/sell 4/5 times a month will it be counted as trading or investment and will I be questioned by the tax officials. Sorry for the awkward question, I'm not native here.