Perhaps you should try some spelling variations:
sach tu » sach thu, cach tu, sach uu
sach ty » sach y, sach thu, xach tay
cao hoi » cau hoi, co hoi, cao hoc
qua cao » qua cac, qua ca, qua cai
cao suc » cao su, cao duc
va hanh » van hanh, va thanh, va danh
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren
suc 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: thu ((sach tu) OR (sach ty)) nang cao hoi. hieu qua cao suc va hanh vi ((cuu tre) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach tu) OR (sach ty)) nang cao hoi. hieu qua cao suc va hanh vi ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach tu) OR (sach ty)) nang cao hoi. hieu qua cao suc va hanh vi ((cuu tre) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: thu ((sach tu) OR (sach ty)) nang cao hoi. hieu qua cao suc va hanh vi ((cuu tre) or (cua tre))*.