Which Opponent has a Round of 4, and a Rules of thai boxing?
CREATE TABLE "partial_kickboxing_record" (
  "result" text,
  "opponent" text,
  "method" text,
  "event" text,
  "date" text,
  "round" text,
  "time" text,
  "location" text,
  "rules" text
);
SELECT "opponent" FROM "partial_kickboxing_record" WHERE "round"='4' AND "rules"='thai boxing';