Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi hanh » thi thanh
cham cuu » cap cuu, chat cua
cham luc » cham soc, nhan luc, chat lua
su sach » so sach, vu sach
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, me hoi
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach thi hanh ((ma hoi) OR (ma hoa)). hieu va ((cham luc) or (cham cuu)) va tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thi hanh ((ma hoi) OR (ma hoa)). hieu va ((cham luc) OR (cham cuu)) va tinh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thi hanh ((ma hoi) OR (ma hoa)). hieu va ((cham luc) or (cham cuu)) va tinh va cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach thi hanh ((ma hoi) OR (ma hoa)). hieu va ((cham luc) or (cham cuu)) va tinh va cua tre*.