When did an away team score 17.8 (110)?
CREATE TABLE "round_21" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "crowd" real,
  "date" text
);
SELECT "date" FROM "round_21" WHERE "away_team_score"='17.8 (110)';