Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dua tren » dung tren
nang mai » nang ma, nang tai, lang mai
tinh dai » trinh dai, tinh da, tinh hai
ve cham » va cham, ve chat, vu cham
va tinh » may tinh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ky nang, ty xang, ty hang
luc va » duc va, tuc va, loc va
ve cam » ve cac, va cam, ve cai

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

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