Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh cac » hang cac, hanh cat, hanh cham
hanh vai » hanh vi, hanh va, hanh tai
sach tai » sach bai, sach tham, sach dao
cua viet » ca viet, hoa viet, cua vat
hanh ca » hanh cat, hanh cua, hanh cad
cac tuc » cac toc, cac tu, cac tac
cac toi » cac thoi
xa hanh » xa thanh, xa khanh, va hanh
vai cua » dai cua, hai cua, lai cua
hieu va » lieu va, hieu qua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tai ((hanh ca) OR (hanh cac)) hoi. hieu va ((cac tuc) or (cac toi)) xa hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tai ((hanh ca) OR (hanh cac)) hoi. hieu va ((cac tuc) OR (cac toi)) xa hanh vai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach tai ((hanh ca) OR (hanh cac)) hoi. hieu va ((cac tuc) or (cac toi)) xa hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: toc sach tai ((hanh ca) OR (hanh cac)) hoi. hieu va ((cac tuc) or (cac toi)) xa hanh vai cua viet*.