Fix #17974

src/vs/workbench/parts/search/browser/searchViewlet.ts

@@ -806,8 +806,20 @@ export class SearchViewlet extends Viewlet {
 			return null;
 		}
 
-		let range = editorControl.getSelection();
-		if (range && !range.isEmpty() && range.startLineNumber === range.endLineNumber) {
+		const codeEditor: ICommonCodeEditor = <ICommonCodeEditor>editorControl;
+		const range = codeEditor.getSelection();
+		if (!range) {
+			return null;
+		}
+
+		if (range.isEmpty() && !this.searchWidget.searchInput.getValue()) {
+			const wordAtPosition = codeEditor.getModel().getWordAtPosition(range.getStartPosition());
+			if (wordAtPosition) {
+				return wordAtPosition.word;
+			}
+		}
+
+		if (!range.isEmpty() && range.startLineNumber === range.endLineNumber) {
 			let searchText = editorControl.getModel().getLineContent(range.startLineNumber);
 			searchText = searchText.substring(range.startColumn - 1, range.endColumn - 1);
 			return searchText;