Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach kem » hanh kem
tinh hai » tinh thai, tinh chat, trinh han
tinh vai » tinh va, tinh bai, tinh lai
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
cac luc » cau luc, coc luc, cac nuoc
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va
ma hoi » mai hoi, xa hoi, ma hoa

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

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