Perhaps you should try some spelling variations:
sach tham » sach nha
van hanh » van thanh, ban hanh, van anh
lang van » dang van, tang van, hoang van
lai cua » dai cua, hai cua, lai chau
duc van » duc va, duc tan, duc manh
tu sach » thu sach, su sach, te sach
va pham » van pham, va phat, va phap
lang xa » lang ha, dang xay
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: tu sach tham ((lang xa) OR (lang van)) hoi. hieu va pham duc van hanh ((bai ca) or (lai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tham ((lang xa) OR (lang van)) hoi. hieu va pham duc van hanh ((bai ca) OR (lai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tham ((lang xa) OR (lang van)) hoi. hieu va pham duc van hanh ((bai ca) or (lai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach tham ((lang xa) OR (lang van)) hoi. hieu va pham duc van hanh ((bai ca) or (lai cua)) triet*.