Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
lang mai » lang dai, lang hai, lang man
cham luc » cham soc, nhan luc, cham cuu
vu cham » va cham, vu kham, tu cham
cua tre » cua te, cuu tre, dua tren
hanh de » hanh ve, hanh kem
luc van » luoc van, luu van, duc van
hieu vu » hieu va, hieu ve, hieu su
mai hoi » mai khoi, dai hoi, lai hoi
sach ty » sach y, sach tu, sach thu
sac ky » cac ky, sai ky

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

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