Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
tinh viet » trinh viet, ninh viet, dinh viet
viet cua » viec cua, viet ca, viet qua
hieu van » hieu va, thien van, lieu va
nang mai » nang ma, nang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
nam luc » nhan luc, nam thuc, nam duoc
va tinh » may tinh
tu sach » thu sach, su sach, te sach
tu sac » tu cac, tu san, tu bac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sac) or (tu sach)) ky nang mai hoi. hieu van ((nam luc) OR (nang luc)) va tinh viet cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (tu sach)) ky nang mai hoi. hieu van ((nam luc) OR (nang luc)) va tinh viet cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sac) or (tu sach)) ky nang mai hoi. hieu van ((nam luc) OR (nang luc)) va tinh viet cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (tu sach)) ky nang mai hoi. hieu van ((nam luc) OR (nang luc)) va tinh viet cua triet*.