use titleExpression_eq instead of skillExpression_eq in marketPlaceJobFilter variable.

Here is the query I used:

{ "query": "query marketplaceJobPostingsSearch($marketPlaceJobFilter: MarketplaceJobPostingsSearchFilter, $searchType: MarketplaceJobPostingSearchType, $sortAttributes: [MarketplaceJobPostingSearchSortAttribute]) { marketplaceJobPostingsSearch(marketPlaceJobFilter: $marketPlaceJobFilter, searchType: $searchType, sortAttributes: $sortAttributes) { totalCount edges { node { id title description category } } pageInfo { hasNextPage endCursor } } }", "variables": { "marketPlaceJobFilter": { "titleExpression_eq": "Google Sheets OR Google Apps Script" }, "searchType": "USER_JOBS_SEARCH", "sortAttributes": [ { "field": "RECENCY" } ] } }