Perhaps you should try some spelling variations:
tinh doi » trinh doc, trinh do, tinh hoc
tu sach » thu sach, su sach, te sach
doi cua » dai cua, hoi cua
va tinh » may tinh
cau loc » hau loc, cau hoc, cau luc
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
loc va » hoc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((nang xa) or (nang ma)) hoi. ((hieu ve) or (lieu va)) cau loc va tinh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang ma)) hoi. ((hieu ve) OR (lieu va)) cau loc va tinh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (nang ma)) hoi. ((hieu ve) or (lieu va)) cau loc va tinh doi cua tre*.