There is something similar in Luke, chapter 4:42, but there it was a crowd of people with no mention of Simon. Mark said that Simon was with some of his companions or fellow disciples (Σίμων καὶ οἱ μετ’ αὐτοῦ) who were hunting or following after or looking for Jesus (καὶ κατεδίωξεν αὐτὸν). When they found him (καὶ εὗρον αὐτὸν), they said to him (καὶ λέγουσιν αὐτῷ) that everyone was seeking, searching, or looking for him. Jesus could not be alone.
This saying of Jesus is exactly the same as in Luke, chapter 11:9-10, indicating a common Q source. Jesus told them to ask (Αἰτεῖτε), and they would get it (καὶ δοθήσεται ὑμῖν). Seek (ζητεῖτε), and they would find (καὶ εὑρήσετε). Knock (κρούετε), and it will be opened (καὶ ἀνοιγήσεται ὑμῖν). Everyone who asked would receive (πᾶς γὰρ ὁ αἰτῶν λαμβάνει) what he asked for. The seeker will find (καὶ ὁ ζητῶν εὑρίσκει) what he is looking for. The one knocking will see it open (καὶ τῷ κρούοντι ἀνοιγήσεται). All is well that ends well. You just need a little effort.