Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hang hai » hoang hai, hang tai, thanh hai
hanh hai » thanh hai, nhanh hai, hanh tai
cham tuc » nham thuc, pham thuc, tham thuc
sach ty » sach y, sach tu, sach thu
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
cao hoi » co hoi, cao hoc, tao hoi
ty nang » ky nang, ty xang, ty hang
tuc va » thuc va, truc va, tuc xa
thiet » thieu

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 ((cao hoi) or (cau hoi)). hieu vu cham tuc va ((hanh hai) OR (hang hai)) va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang ((cao hoi) OR (cau hoi)). hieu vu cham tuc va ((hanh hai) OR (hang hai)) va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang ((cao hoi) or (cau hoi)). hieu vu cham tuc va ((hanh hai) OR (hang hai)) va thiet".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang ((cao hoi) or (cau hoi)). hieu vu cham tuc va ((hanh hai) OR (hang hai)) va thiet*.