While purchasing the first ticket, you can mark the Return button, or after purchasing one-way, you can re-enter the system and purchase the return tickets by examining the reverse route sign with the reverse route sign.
When you search for flights between Hong Kong and İstanbul, all active companies and flight times on the date you entered are listed. You can find the cheapest flight tickets by sorting this list by price.
The most frequently used airline companies from Hong Kong to İstanbul are generally
Türk Hava Yolları,
China Southern Airlines,
IndiGo,
Asiana Airlines,
Oman Air,
Emirates,
Miat Mongolian Airlines,
Air New Zealand,
Philippine Airlines,
Cathay Pacific,
Singapore Airlines,
Korean Air,
Hong Kong Airlines,
Qatar Airways
are companies.