Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach tham
hang tao » hang tai, sang tao, nang tao
tao khoi » tao hoi, thao khoa, lao khoa
phan lap » phan dau
hieu vi » hieu voi, hieu va, hieu ve
va phan » van phan, va phat, va phap
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((sach thi) OR (sach thieu)) hang tao khoi. hieu vi pham duc va phan lap ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((sach thi) OR (sach thieu)) hang tao khoi. hieu vi pham duc va phan lap ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((sach thi) OR (sach thieu)) hang tao khoi. hieu vi pham duc va phan lap ((cua te) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: doc ((sach thi) OR (sach thieu)) hang tao khoi. hieu vi pham duc va phan lap ((cua te) or (cua tu))*.