download github.com/mineralres/protos/src/go/six error

[nengbai]

when I t r y to go run cmd/six_backend/db.go, The errors tell me it's depend on below package, but it Cann't be download. why ?
cmd/six_backend/db.go:6:2: no required module provides package github.com/mineralres/protos/src/go/six; to add it:
go get github.com/mineralres/protos/src/go/six