Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
hieu va » lieu va, hieu qua
hieu ve » hieu van
cu tren » tu tren, dua tren
anh ke » anh le, hanh kem, banh keo
anh ve » hanh ve, anh va, anh viet
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: tu sach ky nang x hoi. ((hieu ve) or (hieu va)) cham duc van ((anh ke) OR (anh ve)) cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((hieu ve) OR (hieu va)) cham duc van ((anh ke) OR (anh ve)) cu tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((hieu ve) or (hieu va)) cham duc van ((anh ke) OR (anh ve)) cu tren*".