Perhaps you should try some spelling variations:
trong marketing » tvqg marketing
tri marketing » tvqg marketing, _ marketing, cuu marketing
thuat dung » thuat hung, thuat ung, thuat xung
dung dung » ung dung, dung ung, dung dong
sach mau » sach dau, sach dao, bach mai
sach my » sach ty, sach moi, sach hay

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: bo ((((sach my) or (sach y))) or (sach mau)) thuat dung dung ((trong marketing) OR (tri marketing))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo ((((sach my) OR (sach y))) OR (sach mau)) thuat dung dung ((trong marketing) OR (tri marketing)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "bo ((((sach my) or (sach y))) or (sach mau)) thuat dung dung ((trong marketing) OR (tri marketing))".
• Adding a wildcard symbol may retrieve word variants: bo ((((sach my) or (sach y))) or (sach mau)) thuat dung dung ((trong marketing) OR (tri marketing))*.