This is the 769th most frequent Czech word.
přišli
"Arrived" or "came" (past tense, plural).
In this sentence, "přišli" is the past tense, plural form of "přijít" (to come), indicating that the friends arrived.
Včera večer přišli moji přátelé na návštěvu.
Yesterday evening, my friends came for a visit.
Here, "přišli" again functions as the past tense, plural form of "přijít", referring to the children returning.
Děti přišli ze školy unavené.
The children came back from school tired.
In this context, "přišli" conveys the idea of 'arriving with an idea or plan', extending the basic sense of 'coming' into a metaphorical usage.