A computer-implemented method performed in connection with a computerized system incorporating a processing unit and a memory, the computer-implemented method involving: using the processing unit to generate a multi-modal language model for co-occurrence of spoken words and displayed text in the plurality of videos; selecting at least a portion of a first video; extracting a plurality of spoken words from the selected portion of the first video; extracting a first displayed text from the selected portion of the first video; and using the processing unit and the generated multi-modal language model to rank the extracted plurality of spoken words based on probability of occurrence conditioned on the extracted first displayed text.