Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
sach thu » sach thieu, sach tham, cach thuc
vai cua » dai cua, hai cua, lai cua
hieu ve » hieu va, hieu van
bang ma » bang may, tang ma, ban ma
ma hoi » mai hoi, xa hoi, ma hoa
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: so ((sach thu) or (sach thue)) bang ma hoi. hieu ve ((kham chua) OR (kham pha)) van hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach thu) OR (sach thue)) bang ma hoi. hieu ve ((kham chua) OR (kham pha)) van hanh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach thu) or (sach thue)) bang ma hoi. hieu ve ((kham chua) OR (kham pha)) van hanh vai cua te".
• Adding a wildcard symbol may retrieve word variants: so ((sach thu) or (sach thue)) bang ma hoi. hieu ve ((kham chua) OR (kham pha)) van hanh vai cua te*.