Ahmad and Impra are both several cuts above Twinings, not expensive (especially as bulk loose-leaf) and can be found in standard grocery stores, or ordered online.

If you've a specialty tea shop nearby, that's all but certainly better, though it can be pricey.

You'll find there's a whole new world out there, and may regret discovering a taste for real whole-leaf teas.

Greens, whites, blacks, fermented, oolongs, darjeelings, matcha, gunpowder, pu'er, etc.

There are also herbal teas, such as rooibos, not made from sinchilla (tea plant), but also tasty.

Best is to buy a bag of loose tea from a tea shop. The leaves are whole, it's not powder. It's usually not hard to find, but they don't sell it at most supermarkets.