Perhaps you should try some spelling variations:
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"co sach ky thuat xung dung tvqg marketing" » "co sach ky thuat xung dung trong marketing", "co sach ky thuat xung dung tri marketing", "co sach ky thuat dung dung tvqg marketing", "co sach ky thuat hung dung tvqg marketing", "co sach ky thuat ung dung tvqg marketing", "co sach ky thuat cung dung tvqg marketing", "co sach ky thuat xung dung tong marketing", "bo sach ky thuat xung dung tvqg marketing", "cuon sach ky thuat xung dung tvqg marketing", "hoc sach ky thuat xung dung tvqg marketing", "co sac ky thuat xung dung tvqg marketing", "co sach y thuat xung dung tvqg marketing", "co sach ty thuat xung dung tvqg 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 sach ky thuat xung dung tvqg marketing") or ("co chu ky thuat song dung tren marketing"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("co sach ky thuat xung dung tvqg marketing") OR ("co chu ky thuat song dung tren marketing")).
• Removing quotes may allow a broader search: (( co sach ky thuat xung dung tvqg marketing ) or ( co chu ky thuat song dung tren marketing )).
• Adding a wildcard symbol may retrieve word variants: (("co sach ky thuat xung dung tvqg marketing") or ("co chu ky thuat song dung tren marketing"))*.