Sound everything out and look up the sounds you are hearing based on many different ways of spelling the sounds, as in "f" or "ph," and as in "k" or "ch."
Remember, too, to work your way through the vowels after the main sound: if "ch" is the main sound you would then look up words with a-e-i-o-u-and y following "ch."
Examples:
> You hear --"a-k"--as in acanthosis; check ac, acc, ach, ak, aq
> You hear--"ace"--as in acebutolol; check ace, aci, ase, asy
> You hear--"acu"--as in acute; check in acu, accu
> You hear--"ad-e"--as in adenovirus; check ade, adi, ady
> You hear--"aero"--as in aerobic; check aro, arro, ary, ero, ery
> You hear--"alla"--as in allachesthesia; check alla, alle, allo, ala, ale, ali, allyl, alo
> You hear--"ambi"--as in ambient; check ambi, ambly, ambe
> You hear--"am-e"--as in ametropia; check ame, ami, amy
> You hear--"ank"--as in ankyloglossia; check anch, ank
> You hear--"ante"--as in antegrade; check ante, anti
> You hear--"a-f"--as in aphasia; check aph, af
> You hear--"apo"--as in apoplexy; check api, apo, ape, appe, appi, appo, apy
> You hear--"antree"--as in antresia; check antre, antri