Perhaps you should try some spelling variations:
may thoi » gay thoi, may thi, tay thoi
cham loc » cham soc, chon loc, hau loc
hanh lai » hanh lam, hanh tai, thanh lap
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
ty mang » ty xang, ty hang, tin mang
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, ban hanh
cham o » cham soc
lai va » loai va, mai va, dai va
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: vu sach ty mang may thoi. hieu ve ((cham loc) OR (cham o)) va hanh lai va thiet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ty mang may thoi. hieu ve ((cham loc) OR (cham o)) va hanh lai va thiet".
• Adding a wildcard symbol may retrieve word variants: vu sach ty mang may thoi. hieu ve ((cham loc) OR (cham o)) va hanh lai va thiet*.