Perhaps you should try some spelling variations:
sach tham » sach nha
hang cau » hang dau, hang ca, nhung cau
na hanh » nha hanh, dna hanh, va hanh
via cua » gia cua, gian cua, giau cua
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, sach thu
ma hanh » va hanh, da hanh, ban hanh
ve tao » ve bao, de tao, ve tac
cua te » cua tu

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) or (sach tham)) hang cau hoi. hieu ve tao duoc ((ma hanh) OR (na hanh)) via cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach tham)) hang cau hoi. hieu ve tao duoc ((ma hanh) OR (na hanh)) via cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach tham)) hang cau hoi. hieu ve tao duoc ((ma hanh) OR (na hanh)) via cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach tham)) hang cau hoi. hieu ve tao duoc ((ma hanh) OR (na hanh)) via cua te*.