Short answer — several places. If you want the exact "yellow polka‑dot" looks people wore at Malaysian Fashion Week, try:

• Malaysian marketplaces and boutiques (good for runway-inspired & local designers)

  • ZALORA Malaysia — big selection of polka‑dot pieces and carries Malaysian designers. (zalora.com.my)
  • Lazada / LazMall — lots of affordable spot prints and sets from local brands. (lazada.com.my)
  • Designer pieces on local platforms (for runway-style options) — e.g., Syomirizwa Gupta and other Malaysian designers appear on ZALORA and similar channels. (zalora.com.my)

• International / designer retailers (ship to the U.S.; good for high‑end runway-level polka dots)

  • The Outnet / Net‑A‑Porter / Farfetch — stock designer polka‑dot dresses and sets (use “yellow polka dot” + designer filters). Example listing on The Outnet. (theoutnet.com)

• High‑street & fast‑fashion (fast delivery, budget to mid price)

  • Mango (has polka‑dot dresses in Malaysia and globally). (shop.mango.com)
  • Zara (yellow dresses and polka patterns appear frequently). (zara.com)
  • Zaful / Rotita / Shein — inexpensive co‑ords and summer sets in “bee”/mustard yellow polka dots. (zaful.com)

• Handmade / vintage / bespoke

  • Etsy — vintage yellow polka‑dot finds and made‑to‑order sellers (good if you want a specific runway vibe). (etsy.com)

Quick tips to find the exact look

• Use precise search terms: “mustard yellow polka dot dress”, “yellow polka‑dot co‑ord set”, “yellow polka dot midi dress”, or “yellow polka dot suit”.
• Filter by color (mustard / sunshine / lemon), pattern (polka/spot), and silhouette (midi, maxi, two‑piece).
• If you saw a Malaysian designer on the runway, search that designer’s name + the show (or check ZALORA / The Outnet / Farfetch for their ready‑to‑buy pieces). (zalora.com.my)

If you want, tell me: 1) whether you prefer budget, midrange or designer, and 2) whether you need it shipped to the U.S. — I’ll pull direct links and match a few exact items in your price range.