Are these sentences correct?

What is more, the learners were convinced that they had already known some of these words, just because they simply looked familiar to them.

According to results we cannot assume that learners know the right meaning just because particular word is commonly and more frequently used.

..they already knew....( niepotrzebny past perfect)
..sounded familiar ..
to THE results, ( comma)
..just because some particular word tends to be more frequently/commonly used (mozna dodac; than/in preference to..)