Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
tu sach » su sach, te sach, tu cach
nang xa » nang x, lang xa, nang ma
han tai » hang tai, nhan tai, van tai
soc va » hoc va, loc va, doc va
va han » va phan, van han, va hanh
tai va » thai va, mai va, tri va

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) OR (thu sach)) ky nang xa hoi. hieu van cham soc va han tai va (thiet or thieu)~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu van cham soc va han tai va (thiet OR thieu).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang xa hoi. hieu van cham soc va han tai va (thiet or thieu)".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu van cham soc va han tai va (thiet or thieu)*.