Perhaps you should try some spelling variations:
xang cao » nang cao, lang cao, quang cao
tu sach » thu sach, su sach, te sach
cao hoi » cau hoi, co hoi, cao hoc
ve cham » va cham, ve chat, ve chim
sach ty » sach y, sach tu, sach thu
vu cham » va cham, vu kham, tu cham
va hanh » van hanh, va thanh, va danh
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: tu sach ty xang cao hoi. hieu ((ve cham) OR (vu cham)) tuc va hanh ((dai va) or (mai va)) thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty xang cao hoi. hieu ((ve cham) OR (vu cham)) tuc va hanh ((dai va) OR (mai va)) thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty xang cao hoi. hieu ((ve cham) OR (vu cham)) tuc va hanh ((dai va) or (mai va)) thiet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty xang cao hoi. hieu ((ve cham) OR (vu cham)) tuc va hanh ((dai va) or (mai va)) thiet*.