Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
su triet » su viet, su tien, ve triet
hieu va » lieu va, hieu qua
tuc van » thuc van, truc van, tuc va
sang ma » tang ma, nang ma, sang tao
hanh de » hanh kem
hanh ve » hanh vi, hanh va, hanh kem
cam tuc » cam xuc, cam tu, nam thuc
va cam » va cham, va cac, va cao

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 y ((sang ma) or (mang may)) hoi. hieu va cam tuc van ((hanh de) OR (hanh ve)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((sang ma) OR (mang may)) hoi. hieu va cam tuc van ((hanh de) OR (hanh ve)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y ((sang ma) or (mang may)) hoi. hieu va cam tuc van ((hanh de) OR (hanh ve)) su triet".
• Adding a wildcard symbol may retrieve word variants: thu sach y ((sang ma) or (mang may)) hoi. hieu va cam tuc van ((hanh de) OR (hanh ve)) su triet*.