riddle - a coarse sieve (as for gravel)

sifter - a household sieve (as for flour)

strainer - a filter to retain larger pieces while smaller pieces and liquids pass through

choose, pick out, select, take - pick out, select, or choose from a number of alternatives; "Take any one of these cards"; "Choose a good husband for your daughter"; "She selected a pair of shoes from among the dozen the salesgirl had shown her"

analyse, analyze, examine, study, canvass, canvas - consider in detail and subject to an analysis in order to discover essential features or meaning; "analyze a sonnet by Shakespeare"; "analyze the evidence in a criminal trial"; "analyze your real motives"

separate - divide into components or constituents; "Separate the wheat from the chaff"

rice - sieve so that it becomes the consistency of rice; "rice the potatoes"

resift - sift anew

riddle, screen - separate with a riddle, as grain from chaff

winnow, fan - separate from chaff; "She stood there winnowing grain all day in the field"

pick over, sieve out - separate or remove; "The customer picked over the selection"

choose, pick out, select, take - pick out, select, or choose from a number of alternatives; "Take any one of these cards"; "Choose a good husband for your daughter"; "She selected a pair of shoes from among the dozen the salesgirl had shown her"