Fraises des bois are what average strawberries aspire to be. They're much smaller than regular strawberries but, despite their size, the tiny wood strawberries are intensely fragrant and flavoured. Because they're so fragile, you probably won't see them in most Hong Kong supermarkets - they spoil within a couple of days of being picked. If you do find the berries in the supermarket, check the package carefully for signs of mould. Occasionally, even if the berries look fine, they have a chemical taste. They're very expensive, partly because they have such a short shelf life, but also because the season for them is brief and, being so small, they are tedious to pick.
Fraises des bois are sometimes called wild strawberries, even though they're often cultivated. If you're lucky enough to have a garden (or even large growing pots) with a sunny area, these berries have a reputation for being easy to grow.
These berries should be enjoyed on their own - just give them a quick rinse under cold water then eat them as soon as possible, before they start to mould. If you have a packet of berries that are less than perfect aesthetically, puree them with a small amount of sugar, fresh lemon juice and a tiny pinch of salt, then use as a sauce for fresh fruit, such as ripe, fragrant peaches or apricots.