Perhaps you should try some spelling variations:
"co sac ky thuat ung dung trong marketing" » "co sac ky thuat ung dung tri marketing", "co sac ky thuat ung dung tvqg marketing", "co sac ky thuat hung dung trong marketing", "co sac ky thuat xung dung trong marketing", "co sac ky thuat song dung trong marketing", "co sach ky thuat ung dung trong marketing", "co cac ky thuat ung dung trong marketing", "cao sach ky thuat ung dung trong marketing", "co sai ky thuat ung dung trong marketing"
"bo sach my thuat dung dung trong marketing" » "bo sach my thuat dung dung tri marketing", "bo sach my thuat dung dung tvqg marketing", "bo sach my thuat hung dung trong marketing", "bo sach my thuat xung dung trong marketing", "bo sach my thuat song dung trong marketing", "bo sach my thuat dung ung trong marketing", "bo sach my thuat dung dong trong marketing", "bo sach my thuat dang dung trong marketing", "bo sach ki thuat dung dung trong marketing", "bo sach va thuat dung dung trong marketing", "co sach my thuat dung dung trong marketing", "hoc sach my thuat dung dung trong marketing", "bo sach y thuat dung dung trong marketing", "bo sach ty thuat dung dung trong marketing", "bo sach mau thuat dung dung trong marketing"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("co sac ky thuat ung dung trong marketing") or ("bo sach my thuat dung dung trong marketing"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("co sac ky thuat ung dung trong marketing") OR ("bo sach my thuat dung dung trong marketing")).
• Removing quotes may allow a broader search: (( co sac ky thuat ung dung trong marketing ) or ( bo sach my thuat dung dung trong marketing )).
• Adding a wildcard symbol may retrieve word variants: (("co sac ky thuat ung dung trong marketing") or ("bo sach my thuat dung dung trong marketing"))*.