Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cam tuc » cam xuc, cam tu, nam thuc
ve cam » ve cham, ve cac, va cam
tuc va » thuc va, truc va, tuc xa
dam va » dam van, nam va
dam ha » nam ha, dam phan

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 ((thi hanh) or (thi thanh)) xa hoi. hieu ve cam tuc va hanh ((dam va) OR (dam ha)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((thi hanh) OR (thi thanh)) xa hoi. hieu ve cam tuc va hanh ((dam va) OR (dam ha)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((thi hanh) or (thi thanh)) xa hoi. hieu ve cam tuc va hanh ((dam va) OR (dam ha)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((thi hanh) or (thi thanh)) xa hoi. hieu ve cam tuc va hanh ((dam va) OR (dam ha)) triet*.