WordNet (r) 3.0 (2006):

thrash about
    v 1: move or stir about violently; "The feverish patient
         thrashed around in his bed" [syn: convulse, thresh,
         thresh about, thrash, thrash about, slash, toss,
         jactitate]

Moby Thesaurus II by Grady Ward, 1.0:

39 Moby Thesaurus words for "thrash about":
   agonize over, be at sea, be uncertain, beat about, blunder, careen,
   career, doubt, falter, feel unsure, flounce, flounder, grope,
   labor, lurch, pitch, pitch and plunge, plunge, puzzle over,
   question, reel, rock, roll, seethe, stagger, struggle, stumble,
   sway, swing, toss, toss and tumble, toss and turn, totter, tumble,
   wallop, wallow, welter, wonder, wonder whether