Better explanation

htdocs/langs/en_US/admin.lang

@@ -68,7 +68,7 @@ SearchFilter=Search filters options
 NumberOfKeyToSearch=Nbr of characters to trigger search: %s
 ViewFullDateActions=Show full dates events in the third sheet
 NotAvailableWhenAjaxDisabled=Not available when Ajax disabled
-AllowToSelectProjectFromOtherCompany=In document, allow to link it to project from another company
+AllowToSelectProjectFromOtherCompany=On document of a thirdparty, can choose a project linked to another thirdparty
 JavascriptDisabled=JavaScript disabled
 UsePopupCalendar=Use popup for dates input
 UsePreviewTabs=Use preview tabs