(Bloomberg) — Chinese mainland investors’ fund flows into Hong Kong stocks have sharply fluctuated in recent weeks, underscoring a lack of conviction to build long-term positions.Onshore investors sold HK$27.4 billion ($3.5 billion) worth of stocks in Hong Kong on Tuesday via a trading link after buying HK$29.7 billion in the previous session. Their quick turnaround this week reflects a similar pattern earlier in the month, when traders dumped shares after a record daily purchase on March 9.The rapid swings suggest investors are still waiting for clearer signs that Hong Kong stocks have bottomed, even as the Hang Seng Index has…