Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cau tren » cu tren, dau tren, ca tren
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
hanh di » hanh vi, hanh de, danh di
hang di » hang doi, hang vi, hang dien
x hoi » xa hoi, o hoi, x ho

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 ky nang x hoi. hieu ve pham duc va ((hanh di) OR (hang di)) ((cau tren) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang x hoi. hieu ve pham duc va ((hanh di) OR (hang di)) ((cau tren) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. hieu ve pham duc va ((hanh di) OR (hang di)) ((cau tren) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. hieu ve pham duc va ((hanh di) OR (hang di)) ((cau tren) or (cua viet))*.