Hi, you don’t need to specify the “count” clause explicitly in Compass UI. Simply put filter criteria and hit enter - it would return all the values matching that criteria and would show:
Displaying documents 1-20 of 150
Assuming, there were 150 records that matched your filter criteria.
However, as suggested by @Massimiliano_Marcon - please click to expand the OPTIONS button and try increasing the MAXTIMEMS from 5000 to 10,000 or something and then see. You could even try combination of SKIP and LIMIT if the data set count returned from your query criteria is extremely very large number.
Otherwise, simply use the MongoDB shell that comes with new version of Compass UI and write the same query that you would use with Robo3T.