Perhaps you should try some spelling variations:
sach doi » sach hoi, sach moi, sach dao
tu sach » thu sach, su sach, te sach
hang vi » hanh vi, hang di, khang voi
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, mang may
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc 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 doi ((nang ma) or (nang cao)) hoi. hieu ve cam xuc va ((hang vi) or (hang va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi ((nang ma) OR (nang cao)) hoi. hieu ve cam xuc va ((hang vi) OR (hang va)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach doi ((nang ma) or (nang cao)) hoi. hieu ve cam xuc va ((hang vi) or (hang va)) cua tre*.