Perhaps you should try some spelling variations:
phan tai » pham tai, nhan tai, phan thi
so sach » so sanh, bo sach, co sach
va phan » van phan, va phat, va phap
ve chat » va chat, van chat
ve cham » va cham, vu cham, ve chim
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
xuc va » duc va, tuc va, luc va
tai va » thai va, mai va, tri va
thiet » thieu

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 y ((nang xa) OR (lang xa)) hoi. hieu ((ve cham) or (ve chat)) xuc va phan tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang xa) OR (lang xa)) hoi. hieu ((ve cham) OR (ve chat)) xuc va phan tai va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((nang xa) OR (lang xa)) hoi. hieu ((ve cham) or (ve chat)) xuc va phan tai va thiet".
• Adding a wildcard symbol may retrieve word variants: so sach y ((nang xa) OR (lang xa)) hoi. hieu ((ve cham) or (ve chat)) xuc va phan tai va thiet*.