Perhaps you should try some spelling variations:
van trinh » van thinh, van tinh, dan trinh
va trinh » va tinh, lap trinh, qua trinh
su triet » su viet, su tien, ve triet
nang xa » nang x, lang xa, nang ma
qua cam » qua cham, qua cac, qua ca
cam luc » cam xuc, cau luc
sac ky » sai ky
van su » dan su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sac ky) or (cac ky)) nang xa hoi. hieu qua cam luc ((va trinh) OR (van trinh)) van su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (cac ky)) nang xa hoi. hieu qua cam luc ((va trinh) OR (van trinh)) van su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sac ky) or (cac ky)) nang xa hoi. hieu qua cam luc ((va trinh) OR (van trinh)) van su triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (cac ky)) nang xa hoi. hieu qua cam luc ((va trinh) OR (van trinh)) van su triet*.