Quordle should be approached in a different way than Wordle. With four puzzles to solve in nine guesses, you can't blindly throw letters at it and expect to win; You will have many more possibilities if you think strategically.
That's also the case in Wordle, of course, but it's even more important in Quordle.
There are two key things to remember.
1. Use several seed words.
First of all, you don't want a single initial word, but it almost certainly two or three initial words.
The first of these should probably be one of Wordle's best opening words, because the same things that make them work well will apply here as well. But after that, you need to select another word or possibly two that use many more common consonants and include the remaining vowels.
For example, I currently use STARE > DOILY > PUNCH. Between them, these three words use 15 of the 26 letters of the alphabet, including the five vowels, Y, and nine of the most common consonants (S, T, R, D, L, P, N, C and H). There are many other options – you may want to include an M, B, F or G instead of the H, perhaps, but something like this should work.
If all goes well, that will give you a good idea of what one or sometimes two of the answers might be. If not, good luck!
2. Limit things
Second, if you are faced with a word whose answer could easily be one of several options (for example, -ATCH, where it could be MATCH, BATCH, LATCH, CATCH, WATCH, HATCH, or PATCH), you will definitely want to guess a word that Narrow down those options.
In Wordle, you can try several of them in succession and hope that one is correct, assuming you have enough guesses left. It's risky, but sometimes it works. Also, it is the only option in hard mode. But in Quordle, this will almost certainly result in failure: you simply don't have enough guesses.
In the above scenario, CLAMP would be a good guess, as it could point the way to four of the seven words in one go.