My parents live in Hong Kong and use canola oil in all their chinese cooking. I suggested to my mom to change the cooking oil, but she says there is no other oil. Readily available oils are canola, sunflower, peanut, corn, grapeseed, sesame. Olive oil can be easily bought here as well, but she won't use it for stir-frying or sauteeing chinese-style. What should she use?

Corn starch, soy sauce, and hoisin sauce are also used in almost all dishes. What are alternatives for these?

TIA!