Learn Russian: Здесь можно найти хорошую парикмахерскую.

Парикмахерская is a substantivized adjective. This means it is used entirely as a noun (a hair salon), but it declines exactly like a standard feminine adjective. In this sentence, it takes the feminine accusative ending -ую because it is the direct object of the verb найти (to find).

Do regular adjectives still agree with substantivized adjectives like парикмахерская?

Yes! Even though парикмахерская looks like an adjective, it acts as a feminine noun. Any adjectives describing it must match its gender, number, and case. That is why хорошая (good) changes to its feminine accusative form хорошую to perfectly match парикмахерскую.

Where does the word парикмахерская come from?

It is built from the noun парикмахер (hairdresser or barber). In Russian, many names for businesses or specific rooms are formed by adding a feminine adjective ending to a root. Historically, this describes an invisible feminine noun like комната (room) or мастерская (workshop).

Why is the perfective verb найти used here instead of the imperfective искать?