Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
thu sach » tu sach, thuat sach, thuoc sach
phan duc » pham duc, phan tu, phan dau
va triet » va thiet, va trien, ve triet
hieu van » hieu va, thien van, lieu va
hac duy » pham duy, phan duy
sach ty » sach y, sach tu, sach thu
minh di » minh ai, minh de, minh duc
ty nang » ky nang, ty xang, ty hang

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 ty nang x ho. hieu van ((hac duy) or (phan duc)) van minh di ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang x ho. hieu van ((hac duy) OR (phan duc)) van minh di ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang x ho. hieu van ((hac duy) or (phan duc)) van minh di ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang x ho. hieu van ((hac duy) or (phan duc)) van minh di ((cua triet) OR (va triet))*.