Come upon and Dig up

Come upon verb - Find unexpectedly.

Dig up and come upon are semantically related In some cases you can use "Dig up" instead a verb "Come upon".

Dig up verb - To come upon after searching, study, or effort.

Come upon and dig up are semantically related in find topic. Sometimes you can use "Come upon" instead a verb "Dig up", if it concerns topics such as lay hands on.