Perhaps you should try some spelling variations:
cham luc » cham soc, nhan luc, cham cuu
su sach » so sach, vu sach
tinh di » tinh doi, trinh di, tinh da
va tinh » may tinh
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va
sang ma » tang ma, nang ma, sang tao
xang ma » tang ma, nang ma, rang ma
luc va » duc va, tuc va, loc va
di cua » dai cua, doi cua, de cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((xang ma) OR (sang ma)) hoi. ((hieu va) OR (hieu qua)) cham luc va tinh di cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((xang ma) OR (sang ma)) hoi. ((hieu va) or (hieu qua)) cham luc va tinh di cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((xang ma) OR (sang ma)) hoi. ((hieu va) or (hieu qua)) cham luc va tinh di cua tre*.