Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
dau tren » dau tien, dau tieng, dau trong
dat tren » dat trong, dua tren
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
va cham » va chat, va tham
soc van » hoc van, oc van, sac van

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y ((nang xa) or (nang ma)) hoi. lieu va cham soc van hanh vi ((dau tren) OR (dat tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((nang xa) OR (nang ma)) hoi. lieu va cham soc van hanh vi ((dau tren) OR (dat tren))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y ((nang xa) or (nang ma)) hoi. lieu va cham soc van hanh vi ((dau tren) OR (dat tren))*".