Perhaps you should try some spelling variations:
tinh doi » trinh doc, trinh do, tinh hoc
su sach » so sach, vu sach
sang ma » tang ma, sang tao, mang may
doi cua » dai cua, hoi cua
va tinh » may tinh
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, nang cao, mang may
bo sach » co sach, hoc sach
ve coc » ve cuoc, ve cac, ve co
luc va » duc va, tuc va, loc va

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