So do I really know Vocab ? - Series

After learning 1-3 vocab I started with do i really know; I am unable to answer questions there, But When i am coming back on vocab mountain I am able to tell the meaning of words. I just started with Vocab mountain only 1-3 is done.

Is it right decision to visit Do i really know series now ? Should I visit it later

Is it because you don’t know synonyms? Why exactly are you struggling with those videos?

Yes synonyms is one reason, other reason which i felt i just learnt is single word explaing it’s meaning. few of words i really didn’t spend time more understanding and also i have learnt them in that sequence when shuffled i am confused

What does this mean?